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Maternal weight gain in pregnancy and risk of obesity among offspring: a systematic review.

1. Introduction

Childhood obesity is a pandemic [1]. Over 155 million children aged 5-17 are overweight or obese worldwide [2]. In the United States, 16.9% children and adolescents aged 2-19 years are obese [3], while, in Europe, 12-36% children aged 7-11 years are overweight or obese. The childhood obesity epidemic has become a public health priority because of its immediate health consequences for children such as increased risk of type 2 diabetes mellitus and heart diseases [4, 5] and its long-term health impact such as increased risks of cardiovascular diseases, cancers and all-cause mortality in adulthood [6-8].

To reverse the obesity epidemic among children, identifying risk factors for prevention is crucial. Obesity is a result of individuals consuming more energy than they expend [9]. This positive energy balance is subject to multiple factors such as genetics, environment, and lifestyle factors [10-12]. In recent years, a growing body of literature suggests that intrauterine environment may also have a profound influence on the development of obesity later in life [13, 14]. One possible mechanism is that a suboptimal intrauterine nutritional environment that may modulate child's energy balance system through altering the developmental programming of appetite control and the metabolism of adiposity and adipocytes in fetuses. Children with the modified energy balance systems may be more vulnerable to obesogenic environment and thus increasing their risk of developing obesity in childhood [13, 14].

Maternal gestational weight gain (GWG), defined as the amount of weight a pregnant woman gained between the time of conception and the onset of labor [15], is one of the key markers of intrauterine nutritional environment. Between 1997 and 2007, approximately 46% of the pregnant US women gained more weight than the Institute of Medicine (IOM) recommendation [16, 17].

In recent years, this health issue has attracted an increasing number of researchers due to the potential impact of GWG on offspring's body weight in childhood [16-18]. Therefore, the objective of this review was to systematically summarize current knowledge regarding the association between GWG and offspring body weight in children aged 2 to 18.9 years from observational studies.

2. Materials and Methods

2.1. Search Strategy. A systematic review of existing cohort studies (prospective and retrospective) was performed following the PRISMA (preferred reporting items for systematic reviews and meta-analysis) statement [19] (see Supplementary Table 1 available online at http://dx .doi.org/10.1155/2014/524939) and the MOOSE (meta-analysis of observational studies in epidemiology) [20] guidelines. One author (EYL) conducted an electronic database search to retrieve English articles from PubMed, Web of Science, CINAHL, and Academic Search Premiere published from inception to March 18, 2013. The search strategies combined "gestational weight gain" or "pregnancy" or "maternal weight gain" with any of the following terms: outcomes (overweight, obesity, adiposity, or body mass index), target population (child, adolescent, offspring), and study design (longitudinal studies, cohort studies, or follow-up studies). Full electronic search strategies were described in Supplementary Table 2. To attain additional eligible articles, experts in the field were contacted; reference lists of located studies and relevant reviews [21, 22] were scanned. The search was limited to English articles published in international peer-reviewed journals. Book chapters, abstracts of conference proceeding, and dissertations were excluded.

2.2. Selection of Studies. To be included, articles had to (1) employ a cohort study design (prospective and retrospective), (2) focus on children aged 2 to 18.9 years, and (3) use GWG as an exposure and child age-and-gender specific BMI or overweight status used as an outcome. The current review focused on studies conducted in children and adolescents aged 2 to 18.9 years because the BMI-for-age percentiles from the Centers for Disease Control and Disease Prevention (CDC) and the International Obesity Task Force (IOTF) all start at age 2. BMI-for-age and overweight status were selected as the primary outcomes of interest because they were widely used in existing studies. Fat mass or waist circumference was not chosen because very few studies focused on these outcomes [23-25]. Studies were excluded if they focused on GWG in relation to child birth weight [26-28] or if the studies examined maternal prepregnancy overweight status rather than GWG in relation to offspring's body composition outcomes [29, 30].

The results from each database search and hand search were entered into Endnote database (Endnote X6, Thomas Reuters, 2012) and duplicated studies were removed. The title and abstract of the remaining studies were screened to identify potential articles for independent assessment of eligibility by two authors (EYL, JXL) and checked by the third author (JHL). Any disagreements were resolved by discussion among authors.

2.3. Data Analysis. The following data were extracted into a summary table by one author (EYL) and checked by another author (JXL): source (year of publication and country in which study was conducted); study characteristics (sample size, time period of the cohort, and child age at follow-up); GWG and child body weight measurements; confounders adjusted; and main findings. We decided not to use formal meta-analytic methods to estimate the effect of the exposure because of the expected heterogeneity in included studies, such as variations in exposure measures, length of follow-up, study population, and analytical methods. Therefore, the present review provided a qualitative evaluation of the longitudinal association between weight gain during pregnancy and child body weight outcomes. When a study presented results of multivariable statistical models, we summarized the findings based on the fully adjusted models. Discrepancies in data extraction were resolved by consensus of all authors.

2.3.1. Methodological Quality Assessment. Two authors (EYL and JXL) independently rated the quality of included studies using an 8-item quality assessment checklist based on a published scale [15]. The quality of each study was graded as high, medium, or low on each of the following domains: background and objective, sample selection, specification of exposure, specification of outcome, data source, follow-up, comparability of analysis, analysis of outcome, and result interpretations.

3. Results

3.1. Summary of the Search. The literature search yielded 2,869 hits. After eliminating 909 duplicates, 2,206 articles were screened by titles and abstracts. An additional 2,148 articles were excluded for not meeting our inclusion criteria. The remaining eligible full-texts articles (n = 58) were carefully reviewed and 38 of these articles were excluded due to (1) inclusion of samples outside targeted age range (n = 2), (2) not using a cohort study design (n = 1), (3) not using child BMI or overweight status as an outcome (n = 12), and (4) not using GWG as an exposure (n = 21). As a final step, contacting expert in the field and screening reference lists of eligible studies (n = 18) yielded an additional article [31]. Thus, a total of 23 articles [23-25, 31-50] were included in the systematic review (Figure 1).

3.2. Characteristics of Included Studies. Study characteristics are presented in Table 1. Fifteen studies [23-25, 32, 33, 35, 39-45, 47, 50] were based on a pregnancy cohort in which pregnant women were recruited during pregnancy and their offspring were followed prospectively during the childhood [51]. Six studies [34, 36-38, 46, 49] used mixed prospective cohort designs, in which maternal GWG was ascertained from medical records, and child's body weight was collected during the follow-up [51]. Three studies [31, 43, 48] used a retrospective design, in which maternal GWG was obtained from past records and data on child's body weight outcomes were either retrieved from medical record or ascertained at the time the study began [51].

Nine out of the 19 studies used data from historic cohorts (i.e., cohorts initiated between 1959 and 1990) [24, 33, 37-39, 43, 44, 46, 47]. Sixteen studies were conducted in the US [25, 31, 33, 35, 36, 38-43, 46-50] and seven studies in Europe [23, 24, 32, 34, 37, 44, 45]. Most of these studies included a reasonably large sample size (n [greater than or equal to] 1000) with three exceptions (n < 700) [42, 43, 49]. Studies conducted in Europe and the US mainly enrolled Caucasian women; all but two [37, 46] enrolled both male and female offspring. Twelve studies focused on younger children (aged 3 to 5 years) [25, 33-36, 39, 40, 42, 43, 45, 48, 50], four studies on older children (aged 6 to 12 years) [23, 32, 46, 47], and three studies concentrated on adolescents (aged 13 to 18 years) [24, 37, 41]. Three studies examined the association of interest across age groups [31, 38, 44].

Three articles came from the Project Viva [25, 35, 40] and were treated as separate studies because they examined different GWG exposures. Two studies [33, 47] drew data from the National Collaborative Perinatal Project and were both included as separate studies because Branum et al. [33] focused on family groups to control for shared genetic or environmental factors. Two articles [42, 50] used data from the Bassett Mothers Health Project; given that both investigations focused on the same GWG exposures and outcomes (but at different ages), they were combined into a single study for analyses and interpretation.

3.3. GWG Measures. GWG is a composite variable that is comprised on measurements of prepregnancy weight, weight, and gestational age at delivery. Methods used to assess GWG varied considerably across the studies. As shown in Table 1, a majority of studies defined total GWG as the difference between mother's weight at delivery or near delivery and mother's prepregnancy weight [15]. Most of the included studies used the last weight measure during prenatal care visits but did not specify the mean duration of measurement time to delivery [23, 25, 31, 35, 38-40, 42, 47-50]. Four studies reporting this information differed in the proximity of last weight measurement prior to delivery (ranged from 37 weeks of gestation to just prior to delivery) which impacts their capacity to measure total weight gain throughout the whole pregnancy [33, 34, 43]. Additionally, one study measured weight within 12 hours after delivery, not accounting for the weight of fetus [37]. Two studies measured weight at 20th week and 30th week of gestation [24, 45]. Four studies asked women to recall their total GWG at postpartum [36, 41, 44, 46]. In terms of the measurement methods, most studies used self-reported prepregnancy weight or weight data abstracted from medical records. Only three studies used objectively measured weight in the early pregnancy [23, 37, 42].

GWG was used as either continuous and/or categorical variables. As a continuous variable, GWG was mainly coded in three ways: total GWG (n = 12) [25, 31-34, 36, 38, 39, 41, 44, 46, 47], net GWG (n = 5) [25, 37, 42, 48, 50], and rate of GWG (kg or lbs/week) (n = 4) [23, 32, 39, 40]. Total GWG is defined as the difference between mother's weight at delivery or near delivery and her prepregnancy weight. Net GWG was calculated by subtracting infant's birth weight from the total GWG, and this accounts for the variation in infant's birth weight. Due to the variation on the timing of weight gain measurements obtained during pregnancy as well as the differences in gestational age at delivery, some studies used the weekly rate of GWG. Weekly rate of GWG is defined as total GWG divided by the duration of pregnancy, expressed as weeks of gestation for the interval such as a trimester or at the visit [39]. Two studies used GWG at 20th week [24] and 30th week [45] of gestation as the exposure. Nine studies adopted the IOM guideline (either 1990 [25, 33, 35, 41, 43, 47] or 2009 [23, 34, 49] guidelines) to categorize maternal total GWG as inadequate, adequate, or excessive GWG. Additionally, two studies analyzed maternal total GWG as a categorical variable using arbitrary cut-off points [38, 46].

3.4. Child Body Weight Measures. Child body weight outcome was expressed as BMI z-score (continuous) in 10 studies and overweight status (categorical) in 13 studies. All studies from USA (n = 16) followed the CDC 2000 cut-off points [25, 31, 33, 35-37, 39-42, 47-50]. Five out of the seven European studies [23, 24, 32, 34, 45] used cut-off points from IOTF/WHO growth chart; one study [44] determined the cut-off points based on national growth chart and two studies [37, 46] used BMI (weight (kg)/height [(m).sup.2]) as the outcome variable. In terms of measurement, 15 studies used objectively measured child body weight [23-25, 33, 34, 36-40, 43, 44, 46, 47, 49], four studies used self-reported [35, 41, 42, 50], and three studies used other anthropometrical measures (i.e., parental-reported [32, 45] or clinically recorded [48]). Only four studies included two or more measurement time points during the entire follow-up period [38, 42, 44, 49] and the remaining studies measured child's body weight once (Table 1).

3.4.1. Methodological Quality Assessment. Three studies [23, 37, 48] were rated as having high methodological quality and 20 studies with medium quality [24, 25, 31-36, 38-47, 49, 50]. Overall, studies did not meet the high quality category because of the use of self-reported measures on GWG and child's body weight outcomes (Table 2).

3.4.2. Total GWG and Offspring's Body Weight Outcomes. Table 3 summarized the strength of associations between various GWG measures and body weight outcomes in offspring. Seven out of eight studies [25, 32, 34, 39, 41, 44, 47] that examined the association between continuous total GWG and offspring's body weight outcomes found a significant positive association. That is, an additional kilogram increase in total GWG increased child's BMI z-score by 0.006 to 0.06 units and elevated the risk of overweight or obesity by 1% to 23% after adjusting for potential confounders (Table 3). Five studies [25, 31, 34, 36, 47] conducted stratified analyses to investigate the modifying effect of prepregnancy BMI on the association between total GWG and child's body weight outcomes (Table 4). One study [36] found that the direct effect of GWG on offspring's BMI z-score was stronger than indirect effects in normal-weight and overweight mothers.

Two studies used an arbitrary cut-off point to classify total GWG. Li et al. [38] examined total GWG in relation to the latent growth trajectory in offspring from age 2 to 12. The odds of having child with early-onset of overweight in mothers who gained [greater than or equal to]20.43 kg during pregnancy was 1.7 times that of mothers who gained between 11.35 and 15.88 kg (i.e., higher probability of being overweight between ages 2 and 6). However, total GWG was not associated with the late-onset of overweight in offspring (i.e., lower probability of overweight after 8 years of age). Stuebe et al. [46] categorized total GWG into <10, 10-14, 15-19, 20-29, 30-39, and [greater than or equal to]40 lbs. Their findings indicated a U-shape association between total GWG and offspring's weight status. Using mothers who gained 15-19 lbs as a reference group, the risk of overweight at age 18 significantly increased in offspring of mothers who gained <10 lbs (adjusted odds ratio (AOR): 1.51, 95% CI: 1.00-2.30), 10-14 lbs (AOR: 1.56, 95% CI: 1.13-2.16), and [greater than or equal to]40 lbs (AOR: 1.68, 95% CI: 1.13-2.52).

3.4.3. Net GWG and Offspring's Body Weight Outcomes. Less evidence exists for an association between net GWG and child's body weight outcomes. Four studies [25, 31, 37, 48] demonstrated a positive relationship between net GWG and offspring body weight outcomes, three of which achieved statistical significance [25, 37, 48]. Increments in net GWG were associated with 0.01 to 0.07 unit increase in children's BMI z-score (Table 3).

The effect of maternal prepregnancy BMI on the association between net GWG and offspring's body weight outcomes was examined in one study. Lawlor et al. [37] found that, in the between-family model (participants from different families), the positive association between net GWG and offspring BMI at 18 years of age was stronger in normal-weight mothers than overweight mothers. In the within-family model (siblings from the same family), the positive association was retained in overweight mothers but not in normal-weight mothers (Table 4).

3.4.4. Rate of GWG and Offspring's Body Weight Outcomes. Four studies [23, 32, 39, 40] investigated the association between rate of GWG and offspring's bodyweight outcomes. Although the calculation of rate of GWG varied among studies, these studies consistently demonstrated that high rate of GWG in early- and mid-pregnancy was associated with increased BMI z-score and elevated risk of overweight risk among offspring, while a null association was observed between rate of GWG at late pregnancy and child's body weight outcomes (Tables 3 and 4).

3.4.5. IOM Recommended GWG and Offspring's Body Weight Outcomes. The evidence for an association between excessive GWG and offspring body weight outcomes was less than and not as consistent as total GWG. Eight studies [23, 31, 33, 34, 41, 43, 47, 48] compared the effects of excessive GWG versus adequate GWG on child's body weight outcomes, six of which achieved statistical significance [23, 31, 34, 41, 43, 47]. Offspring born to mothers who gained excessive weight during pregnancy had increased BMI z-scores (0.14 to 0.64 units) and elevated risks of overweight or obesity (27% to 73%) compared to offspring whose mothers gained adequate weight (Table 3).

Three studies [25, 35, 49] compared the effects of excessive GWG on offspring's risk of overweight with a different referent group. Lindberg and colleagues [49] compared the effects of excessive GWG and nonexcessive GWG (adequate GWG plus inadequate GWG) on offspring's risk of overweight between 5 and 8 years of age. The child's risk of overweight was 73% higher in children exposed to excessive GWG than those who did not. Two studies used data from Project Viva. Gillman et al. [35] compared the effects of excessive GWG versus nonexcessive GWG on offspring's risk of overweight and found a null association. Oken et al. [25] found that children exposed to excessive GWG had higher BMI z-score (0.47 units) and elevated risk of overweight (4-fold) than children exposed to inadequate GWG.

Eight studies [23, 31, 33, 34, 41, 43, 47, 48] showed mixed findings while examining the association between inadequate GWG and offspring body weight outcomes. Five studies [31, 33, 34, 43, 47] found a null association; three studies [23, 41, 48] found a negative association (0.06 to 0.21 units reductions in child's BMI z-score) (Table 3). Two studies [34, 47] conducted stratified analyses and found that the effects of excessive GWG on offspring's body weight outcome did not vary by maternal prepregnancy BMI (Table 4).

3.4.6. Other GWG Measures and Offspring's Body Weight Outcomes. Laitinen et al. [24] found that an additional kilogram increase in total GWG during the first 20 weeks of pregnancy increased offspring's odds of developing overweight by 3%. Stamnes Kopp and colleagues [45] showed that total GWG at 30 weeks of gestation was associated with 0.02 unit increments in offspring's BMI at age 3.

4. Discussion

This systematic review presents a summary of existing evidence on the associations of maternal weight gain during pregnancy with offspring body weight outcomes between 2 and 18.9 years from observational cohort studies. Overall, 23 studies met our inclusion criteria. Consistent with previous reviews [21, 22], we also found that higher total GWG significantly increased BMI z-score (0.006 to 0.06 units) and increased risk of overweight or obesity (1% to 23%). Compared to offspring whose mothers gained adequate weight during pregnancy, children of mothers who gained excessive weight had significantly higher BMI z-score (0.74 to 1.73 units) and elevated risk of overweight or obesity (1% to 57%).

A new finding in the present review is the potential impact of rate of GWG on offspring's body weight outcomes. Although an insufficient number of studies (n = 4) are available to draw a conclusion, they consistently demonstrated that high rates of GWG in early- and mid-pregnancy had strong adverse effects on offspring body weight outcomes. The underlying mechanisms regarding this association remain to be defined. Andersen and colleagues [32] performed path analyses and confirmed a direct pathway from rates of GWG in the early- and mid-pregnancy to offspring's body weight outcomes. We speculate that high rates of GWG in early- and mid-pregnancy increased maternal fat deposition and may have altered intrauterine environment for the development of fetal adipose tissues. Theoretically, maternal GWG can affect fetal adiposity accumulation in two possible pathways. The first one is direct transfusion of free fatty acids from the mother to fetus [52]. For underweight and normal weight women (prepregnancy BMI < 25 kg/[m.sup.2]), GWG in the early- and mid-pregnancy is disproportionately fat [53]. The fat mainly deposits in mother's hips, back, and upper thighs as a caloric reserve for late pregnancy and lactation [53]. Meanwhile, mid-pregnancy is recognized as a critical period when fetal fat tissue begins to grow [54, 55]. High rates of GWG in early- and mid-gestational periods could lead to excessive maternal fat deposition that may increase the transmission of free fatty acid from mother to fetus. The second pathway is the synthesis of free fatty acids from substrates such as glucose provided by the mother [52]. Excessive fat deposition during early pregnancy could reduce maternal insulin sensitivity and glucose tolerance [56, 57] to a greater extent than the normal metabolic sequelae of pregnancy. This loss of metabolic control could translate into elevated maternal glucose concentration (i.e., glycemic excursions) which exposes the fetus to an increased glucose supply [56, 57]. Both increased transfusion of lipid and increased supply of glucose from the mother may alter the development of fat cells in fetus, thus resulting in a permanent increase in fetus's capacity to form new cells in adipose depots in postnatal life [54, 58]. However, intensive studies are needed to test these speculations.

The current findings should be interpreted with caution due to several methodological concerns. One notable methodological concern is the failure to adjust for shared familial characteristics. In this review, only two studies employed a between- and within-family design to control for shared familial characteristics. Branum et al. [33] found that the significant association between total GWG and child's BMI z-score became nonsignificant after adjusting for the shared familial characteristics. These results indicated that the positive association between maternal total GWG and offspring's BMI z-score maybe entirely due to shared genetics and environmental (e.g., family lifestyle) factors rather than the intrauterine environment. Lawlor et al. [37] found that the significant association disappeared in normal-weight mother but it remained significant in overweight mothers. These findings implied that, in normal-weight mother, the association between net GWG and offspring BMI is largely due to shared familial risk factors, whereas the association in the children of overweight and/or obese mothers is driven by the exposure to both familial characteristics and intrauterine environment. A recently published study [59] examined the independent effects of GWG on offspring body weight outcomes at 11.9 years of age in 42,133 women and their 91,045 offspring, using a within-family design to minimize confounding effects of shared familial characteristics. The results showed that total GWG significantly increased offspring's BMI z-score by 0.022 units and elevated their risk of overweight by 0.7% at 11 years of age. When classifying total GWG into categories (<6 kg, [greater than or equal to]12 to [less than or equal to] 18, and >18) variable, offspring BMI increased by 0.43 units and the risk of overweight or obesity increased by 8% when comparing children born to mothers who gained >18 kg during pregnancy to those whose mothers gained <6 kg. These associations were independent of child birth weight and other covariates (e.g., gestational age, maternal smoking, parity, child

age, child BMI measured at earlier ages, etc.). These findings confirmed that, after adjusting for familial characteristics, overnutrition in pregnancy could program the fetus for an increased lifetime risk for overweight or obesity, though the magnitude of this effect may be small. Additionally, these studies also demonstrated that introducing shared familiar characteristics into the analyses significantly attenuated the magnitude of associations between GWG and offspring's body weight outcomes. Thus, this important confounding variable needs to be measured and adjusted in future studies.

Shared familial characteristics consist of both genetics and/or environmental factors such as lifestyle. Since none of the studies in our review has adjusted genetic factors as covariates, we are not able to examine its modifying effects on the association of interest. Lifestyle factors such as offspring's physical activity are consistently shown to be a significant predictor of the development of childhood obesity [60]. Besides, there is a strong correlation between maternal lifestyle and offspring behaviors [61, 62]. Recent research has suggested that maternal lifestyles have dramatically changed over the last half century. Maternal activity has decreased significantly over the past 50 years, with a concomitant increase in sedentary behaviors [63, 64]. Additionally, maternal self-reported dietary consumption of away-from-home foods (e.g., packaged and convenience foods like frozen pizza) [65], numbers of eating occasions, and portion sizes per eating occasion have increased significantly over the last 30 years [66]. These changes may have significant effects on childhood lifestyle behaviors such as physical activity, dietary behaviors, and consequent obesity. In the current study, only four studies [25, 34, 36, 41] controlled for child's lifestyle factors (i.e., subjectively measured physical activity and consumptions of unhealthy foods) in the analyses, and these studies found that these factors did not alter the association between GWG and child's body weight outcomes. However, the null association could be due to the attenuation induced via poor measurement (e.g., self-report measures tend to overestimate physical activity and underestimate intake of unhealthy food in children). More research is needed to verify which shared familial characteristics are influential to the association between maternal GWG and offspring body weight outcomes.

Additionally, none of the included studies has reported whether the study is powered to detect expected difference on the primary outcome and interactive effects by maternal prepregnancy BMI. By focusing exclusively or predominantly on Caucasian women, well-educated women, and nonobese women, the extant literature is not generalizable to high risk population such as African Americans, lower income, and overweight and obese women who are more likely to exceed weight gain recommendations during pregnancy than their counterparts [16, 67-69].

Strengths and Limitations. Compared to recently published meta-analyses [21, 22], our review has several strengths such as its focus on cohort studies and careful methodological examination of published studies in terms of quality and timing of GWG measurements, adjustment of confounding variables, statistical analyses, and associated interpretations. As with any study, this review has limitations. Publication bias maybe presented as the current review only included English language and published peer-reviewed journal articles. The heterogeneity in the study samples, exposures, and outcome measures included in this review limited the interpretation of the evidence and prevented the use of meta-analytical methods. The semiquantitative reporting in this review provides only an arbitrary classification of the associations and focuses more on the direction of association rather than magnitude. Several studies have drawn data from the same cohort studies, for example, the Project Viva or National Collaborative Perinatal Project, which may introduce the issue of overrepresentation and bias into the analysis sample.

5. Conclusions

The current findings suggest that GWG is a potential risk factor to prevent childhood obesity. Additionally, GWG appears to be more strongly associated with offspring's body weight outcomes during early- and mid-pregnancy than late-pregnancy, and future studies are encouraged to examine the critical timing in which GWG had the strongest impact on child's body weight outcomes. Future research should also consider the following issues: adjusting confounding effects of shared familial characteristics, improving quality of the measurement on maternal prepregnancy weight, examining the underlying mechanism or pathways, and quantifying the impact among high risk population such as African American, obese, and low income women.

http://dx.doi.org/10.1155/2014/524939

Conflict of Interests

The authors declare that there is no conflict of interests regarding the publication of this paper.

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Erica Y. Lau, (1) Junxiu Liu, (2) Edward Archer, (3) Samantha M. McDonald, (1) and Jihong Liu (2)

(1) Department of Exercise Science, Arnold School of Public Health, University of South Carolina, Columbia, SC 29208, USA

(2) Department of Epidemiology and Biostatistics, Arnold School of Public Health, University of South Carolina, 915 Greene Street, Room 459 Discovery Building, Columbia, SC 29208, USA

(3) Nutrition Obesity Research Center, University of Alabama at Birmingham, Birmingham, AL 35233, USA

Correspondence should be addressed to Jihong Liu; jliu@mailbox.sc.edu

Received 22 July 2014; Revised 11 September 2014; Accepted 14 September 2014; Published 2 October 2014

Academic Editor: Li Ming Wen

TABLE 1: Cohort studies on maternal weight gain during pregnancy
and offspring's body weight outcomes.

Authors, year, country,    Sample size    Child age at
and study design           and time       follow-up
                           period

Li et al. 2007, USA        1,739          2-12 years
(mixed) [38]               (1986-2000)

Oken et al. 2007, USA      1,044          3 years
(pros) [25]                (1999-2002)

Gillman et al. 2008,       1,110          3 years
USA (pros)[35]             (1999-2002)

Oken et al. 2008, USA      11,994         9-14 years
(pros) [41]                (1996-1999)

Wrotniak et al. 2008,      10,226         7 years
USA (pros) [47]            (1959-1965)

Oken et al. 2009, USA      2,012          3 years
(pros) [40]                (1999-2002)

Olson et al. 2009, 2010,   321            4 years
USA (pros) [42, 50]        (1997-1998)

Stuebe et al. 2009, USA    26,506         7 years
(mixed) [46]               (1989-2001)

Fraser et al. 2010, UK     5,154          9 years
(pros) [23]                (1991-1992)

Magerison Zilko et al.     4496           2-20 years
2010, USA (retro) [31]     (1972-2000)

Schack-Nielsen et al.      4,234          1-14 years
2010, Denmark (pros)       (1959-1961)
[44]

Andersen et al. 2011,      9,869          7 years
Denmark (pros)[32]         (1996-2002)

Branum et al. 2011, USA    5,917          4 years
(pros) [33]                (1959-1965)

Lawlor et al. 2011,        14,6894        18 years
Sweden (mixed) [37]        (1973-2005)

Ronney et al. 2011, USA    450 (1988)     4-5 years
(retro) [43]

Ensenauer et al. 2013,     6,837          5 years
Germany (mixed) [34]       (2009-2011)

Hinkle et al. 2012, USA    3,600          5 years
(mixed) [36]               (2001-2006)

Laitinen et al. 2012,      6,637          16 years
Finland (pros) [24]        (1985-2002)

Linberg et al. 2012,       471 (2004)     5-8 years
USA (mixed) [49]

Magerison-Zilko et al.     3,015          5 years
2012, USA (pros) [39]      (1959-1967)

Stamnes Kopp et al.        5,898          3 years
2012, Norway (pros) [45]   (1999-2009)

Ehrenthal et al. 2013,     3,320          4 years
USA (retro) [48]           (2004-2007)

Authors, year, country,    Definition of gestational
and study design           weight gain (GWG)

Li et al. 2007, USA        Self-reported weight before
(mixed) [38]               delivery minus self-
                           reported prepregnancy
                           weight

Oken et al. 2007, USA      Medical record retrieved
(pros) [25]                last prenatal weight minus
                           self-reported prepregnancy
                           weight

Gillman et al. 2008,       Medical record retrieved
USA (pros)[35]             last prenatal weight minus
                           prepregnancy weight

Oken et al. 2008, USA      Self-reported total GWG
(pros) [41]

Wrotniak et al. 2008,      Weight measured at delivery
USA (pros) [47]            minus self-reported
                           prepregnancy weight

Oken et al. 2009, USA      Medical record retrieved
(pros) [40]                last prenatal weight minus
                           self-reported prepregnancy
                           weight

Olson et al. 2009, 2010,   Measured weight at last
USA (pros) [42, 50]        prenatal visit minus first
                           measured weight in the
                           first trimester

Stuebe et al. 2009, USA    Self-reported total GWG
(mixed) [46]

Fraser et al. 2010, UK     Measured weight at last
(pros) [23]                prenatal visit minus
                           measured weight at first
                           prenatal visit

Magerison Zilko et al.     Self-reported weight at
2010, USA (retro) [31]     delivery minus self-
                           reported prepregnancy
                           weight

Schack-Nielsen et al.      Self-reported total GWG
2010, Denmark (pros)
[44]

Andersen et al. 2011,      Self-reported total GWG
Denmark (pros)[32]

Branum et al. 2011, USA    Measured weight at last
(pros) [33]                prenatal visit within 3 wk
                           of delivery minus
                           self-reported prepregnancy
                           weight

Lawlor et al. 2011,        Measured weight within 12 h
Sweden (mixed) [37]        after delivery minus the
                           first antenatal clinic
                           assessment (10 wk
                           gestation)

Ronney et al. 2011, USA    Measured weight prior to
(retro) [43]               delivery minus
                           self-reported prepregnancy
                           weight

Ensenauer et al. 2013,     Measured weight at an
Germany (mixed) [34]       average of 38-wk of
                           gestation minus measured
                           prepregnancy weight

Hinkle et al. 2012, USA    Total GWG from birth
(mixed) [36]               certificates (81%) plus
                           maternal report (19%) at
                           9-month postpartum

Laitinen et al. 2012,      Measured weight at 20-wk
Finland (pros) [24]        gestation minus
                           self-reported prepregnancy
                           weight

Linberg et al. 2012,       Medical record retrieved
USA (mixed) [49]           weight at delivery minus
                           recorded prepregnancy
                           weight

Magerison-Zilko et al.     Medical record retrieved
2012, USA (pros) [39]      last prenatal weight minus
                           self-reported prepregnancy
                           weight

Stamnes Kopp et al.        Self-reported weight at
2012, Norway (pros) [45]   30-week pregnancy minus
                           self-reported prepregnancy
                           weight

Ehrenthal et al. 2013,     Self-reported weight at
USA (retro) [48]           delivery minus
                           self-reported prepregnancy
                           weight

Authors, year, country,    GWG variable
and study design

Li et al. 2007, USA        Total GWG (kg)
(mixed) [38]               (i) < 6.8
                           (ii) 6.81-11.34
                           (iii) 11.35-15.88 (ref)
                           (iv) 15.89-20.42
                           (v) [greater than or equal
                           to] 20.43

Oken et al. 2007, USA      Total GWG (kg)
(pros) [25]                Net GWG (total GWG minus
                           infant birth weight) IOM
                           1990
                           (i) Excessive
                           (ii) Adequate
                           (iii) Inadequate (ref)

Gillman et al. 2008,       IOM 1990
USA (pros)[35]             (i) Excessive
                           (ii) Nonexcessive (Ref)

Oken et al. 2008, USA      Total GWG (lbs)
(pros) [41]                IOM 1990
                           (i) Excessive
                           (ii) Adequate (Ref)
                           (iii) Inadequate

Wrotniak et al. 2008,      Total GWG (kg)
USA (pros) [47]            IOM 1990
                           (i) Excessive
                           (ii) Adequate (Ref)
                           (iii) Inadequate

Oken et al. 2009, USA      Rate of GWG (kg/week)
(pros) [40]

Olson et al. 2009, 2010,   Net GWG (kg)
USA (pros) [42, 50]

Stuebe et al. 2009, USA    Total GWG (lbs)
(mixed) [46]               (i) < 10
                           (ii) 10-14
                           (iii) 15-19 (Ref)
                           (iv) 20-29
                           (v) 30-40
                           (vi) > 40

Fraser et al. 2010, UK     Rates of GWG (g/week)
(pros) [23]                IOM 2009
                           (i) Excessive
                           (ii) Adequate (Ref)
                           (iii) Inadequate

Magerison Zilko et al.     Total GWG (kg)
2010, USA (retro) [31]     IOM (2009)
                           (i) Excessive
                           (ii) Adequate (Ref)
                           (iii) Inadequate

Schack-Nielsen et al.      Total GWG (kg)
2010, Denmark (pros)       (i) < 6
[44]                       (ii) 6-8
                           (iii) 9-10
                           (iv) 11-12
                           (v) 13-15
                           (vi) [greater than or equal
                           to] 16 kg The values of
                           5.5, 7.0, 9.5, 11.5, 14.0,
                           and 16.5 were assigned mid-
                           points

Andersen et al. 2011,      Total GWG rates of GWG [kg
Denmark (pros)[32]         in early (12-20 weeks) and
                           mid-pregnancy (25-32
                           weeks)]

Branum et al. 2011, USA    Total GWG
(pros) [33]                IOM 1990
                           (i) Excessive
                           (ii) Adequate (Ref)
                           (iii) Inadequate

Lawlor et al. 2011,        Net GWG (kg)
Sweden (mixed) [37]

Ronney et al. 2011, USA    IOM 1990
(retro) [43]               (i) Excessive
                           (ii) Adequate (Ref)
                           (iii) Inadequate

Ensenauer et al. 2013,     Total GWG
Germany (mixed) [34]       IOM 2009
                           (i) Excessive
                           (ii) Adequate (Ref)
                           (iii) Inadequate

Hinkle et al. 2012, USA    Total GWG (kg)
(mixed) [36]

Laitinen et al. 2012,      GWG at 20-week gestation
Finland (pros) [24]        (kg) (quartiles were used)

Linberg et al. 2012,       IOM 2009
USA (mixed) [49]           (i) Excessive
                           (ii) Not excessive (Ref)

Magerison-Zilko et al.     Total GWG
2012, USA (pros) [39]      trimester-specific rates of
                           GWG

Stamnes Kopp et al.        GWG at 30-week gestation
2012, Norway (pros) [45]   (kg)

Ehrenthal et al. 2013,     Net GWG (adjusted for
USA (retro) [48]           gestational age) (kg) IOM
                           2009
                           (i) Excessive
                           (ii) Adequate (Ref)
                           (iii) Inadequate

Authors, year, country,    Child body weight measure
and study design

Li et al. 2007, USA        BMI z-score based on
(mixed) [38]               measured height and weight

                           Early-onset OW: BMI
                           [greater than or equal to]
                           95th PCTL persisted from 2
                           to 8 years

                           Late-onset OW: BMI [greater
                           than or equal to] 95th PCTL
                           starting at 8 years (CDC)

Oken et al. 2007, USA      BMI z-score based on
(pros) [25]                measured height and weight
                           OW: BMI [greater than or
                           equal to] 95th PCTL (CDC)

Gillman et al. 2008,       BMI z-score based on self-
USA (pros)[35]             reported height and weight
                           OW: BMI [greater than or
                           equal to] 95th PCTL (CDC)

Oken et al. 2008, USA      BMI o score based on self-
(pros) [41]                reported height and weight
                           OW: BMI 85th to [less than
                           or equal to] 95th PCTL OB:
                           BMI > 95th PCTL (CDC)

Wrotniak et al. 2008,      BMI z-score based on
USA (pros) [47]            measured height and weight
                           OW: BMI [greater than or
                           equal to] 95th PCTL (CDC)

Oken et al. 2009, USA      BM z-score based on
(pros) [40]                measured height and weight
                           OB: BMI > 95th PCTL (CDC)

Olson et al. 2009, 2010,   BMI o score based on self-
USA (pros) [42, 50]        reported height and weight
                           OW: BMI 85th to < 95th PCTL
                           OB: BMI [greater than or
                           equal to] 95th PCTL (CDC)

Stuebe et al. 2009, USA    BMI based on measured
(mixed) [46]               height and weight OW: BMI
                           [greater than or equal to]
                           25 to < 30 kg/[m.sup.2] OB:
                           BMI > 30 kg/[m.sup.2] (CDC)

Fraser et al. 2010, UK     BMI based on measured
(pros) [23]                height and weight (IOTF)

Magerison Zilko et al.     BMI z-score based on
2010, USA (retro) [31]     parent-reported or measured
                           height and weight OW: BMI
                           [greater than or equal to]
                           85th PCTL (CDC)

Schack-Nielsen et al.      BMI z-score based on
2010, Denmark (pros)       measured height and weight
[44]                       (British 1990 growth chart)

Andersen et al. 2011,      BMI z-score based on
Denmark (pros)[32]         parent-reported height and
                           weight (IOTF)

Branum et al. 2011, USA    BMI z-score based on
(pros) [33]                measured height and weight
                           (CDC)

Lawlor et al. 2011,        BMI based on measured
Sweden (mixed) [37]        height and weight (CDC)

Ronney et al. 2011, USA    BMI z-score based on
(retro) [43]               measured height and weight
                           OB: [greater than or equal
                           to] 85th PCTL

Ensenauer et al. 2013,     BMI z-score based on
Germany (mixed) [34]       measured height and weight
                           OW: BMI [greater than or
                           equal to] 90th PCTL. OB:
                           BMI [greater than or equal
                           to] 97th PCTL (IOTF)

Hinkle et al. 2012, USA    BMI c score based on
(mixed) [36]               measured height and weight
                           OW: BMI 85th to < 95th
                           PCTL. OB: BMI [greater than
                           or  equal to] 95th PCTL
                           (CDC)

Laitinen et al. 2012,      BMI z-score based on
Finland (pros) [24]        measured height and weight
                           (IOTF)

Linberg et al. 2012,       BMI z-score based on
USA (mixed) [49]           measured height and weight
                           OW: BMI [greater than or
                           equal to] 85th PCTL (CDC)

Magerison-Zilko et al.     BMI z-score based on
2012, USA (pros) [39]      measured height and weight
                           OW: BMI [greater than or
                           equal to] 85th PCTL (CDC)

Stamnes Kopp et al.        BMI based on parent-
2012, Norway (pros) [45]   reported height and weight

Ehrenthal et al. 2013,     BMI z-score based on
USA (retro) [48]           medical record retrieved
                           height and weight (CDC)

Authors, year, country,    Confounders adjusted
and study design

Li et al. 2007, USA        Maternal age, alcohol
(mixed) [38]               consumption during
                           pregnancy, education,
                           family net incomeO and
                           prepregnancy BMI, and

                           smoking during pregnancy;
                           child's birth order, birth
                           weight, birth year,
                           breastfeeding, gestational
                           age, race, and sex

Oken et al. 2007, USA      Mother's glucose tolerance,
(pros) [25]                marital status,
                           prepregnancy BMI, SES,
                           smoking, and race; paternal
                           BMI; and child
                           breastfeeding duration,
                           cesarean section, daily
                           television viewing time,
                           fast food and sugar
                           beverage intake,
                           gestational fetal growth,
                           gestational length, and sex

Gillman et al. 2008,       Maternal education,
USA (pros)[35]             prepregnancy BMI, smoking
                           during pregnancy, and SES;
                           child breastfeeding
                           duration, daily sleep
                           during infancy, and race

Oken et al. 2008, USA      Maternal age, education,
(pros) [41]                SES, gestational diabetes,
                           marital status,
                           prepregnancy BMI, smoking,
                           and paternal education; and
                           child age in 1996, birth
                           weight, breastfeeding,
                           daily sugar sweetened
                           beverage intake, fried food
                           away from home, gestational
                           age, maturity, hours of TV
                           and video, physical
                           activity, and race

Wrotniak et al. 2008,      Maternal age, prepregnancy
USA (pros) [47]            BMI, parity, race, and
                           smoking; child age at 7-
                           year assessment, birth
                           weight, gestational age,
                           and sex

Oken et al. 2009, USA      Prepregnancy BMI
(pros) [40]

Olson et al. 2009, 2010,   Maternal overweight at
USA (pros) [42, 50]        early pregnancy, SES,
                           smoking during pregnancy,
                           and SES; child birth
                           weight, breastfeeding for
                           at least 6 months, and
                           gestational age

Stuebe et al. 2009, USA    Maternal age at child
(mixed) [46]               birth, prepregnancy BMI,
                           maternal age at child's
                           birth, nausea and smoking
                           during pregnancy, family
                           history of diabetes,
                           parental BMI and education
                           level, and mother living
                           with father at time of
                           child's birth; child birth
                           weight and birth order

Fraser et al. 2010, UK     Maternal age, delivery
(pros) [23]                mode, parity, prepregnancy
                           BMI, parity, smoking during
                           pregnancy, SES, and GWG in
                           the previous pregnancy;
                           child birth weight and
                           gestational age

Magerison Zilko et al.     Maternal age, education,
2010, USA (retro) [31]     poverty status, length of
                           gestation, prepregnancy
                           BMI, and race, smoking
                           during pregnancy; child sex
                           and year of birth; and
                           weighted for sampling
                           proportion

Schack-Nielsen et al.      Maternal age, edema during
2010, Denmark (pros)       prepregnancy, marital
[44]                       status, SES, and smoking
                           during pregnancy; parental
                           education, prepregnancy
                           BMI, and prematurity; and
                           child birth weight,
                           gestational age, and sex

Andersen et al. 2011,      Maternal age, parity,
Denmark (pros)[32]         smoking during pregnancy,
                           prepregnancy BMI, SES, and
                           paternal BMI; child age,
                           birth weight,
                           breastfeeding, gestational
                           age, weight at 5 and 12
                           months, and sex

Branum et al. 2011, USA    Maternal age, parity,
(pros) [33]                prepregnancy BMI, race,
                           SES, and smoking; child
                           birth weight, gestational
                           age, and sex

Lawlor et al. 2011,        Maternal age, education,
Sweden (mixed) [37]        gestational diabetes,
                           parity, and early-
                           pregnancy BMI; child birth
                           weight, gestational age,
                           and year of birth

Ronney et al. 2011, USA    Maternal marital status,
(retro) [43]               GWG in first 4 months and
                           smoking, during pregnancy;
                           child insurance status at
                           birth and sex

Ensenauer et al. 2013,     Maternal age and smoking
Germany (mixed) [34]       during pregnancy; child
                           age, birth weight
                           breastfeeding, TV viewing,
                           physical activity, and SES

Hinkle et al. 2012, USA    Maternal age, race, parity,
(mixed) [36]               marital status, education,
                           participation in special
                           supplement nutrition
                           program for women and
                           child, smoking at the last
                           3 months of pregnancy, and
                           postpartum exercise habits;
                           child's exercise habit; and
                           child birth weight,
                           breastfeeding, gestational
                           age, sugar-sweetened
                           beverage intake, fast food
                           intake, and TV viewing

Laitinen et al. 2012,      Maternal education, glucose
Finland (pros) [24]        metabolism, hemoglobin at
                           8-10 weeks of gestation,
                           parity, prepregnancy BMI,
                           and smoking; child's sex

Linberg et al. 2012,       Maternal education,
USA (mixed) [49]           gestational diabetes,
                           prepregnancy BMI, and
                           smoking before and during
                           pregnancy; child's birth
                           weight and breastfeeding
                           duration

Magerison-Zilko et al.     Maternal age, education,
2012, USA (pros) [39]      marital status, parity,
                           prepregnancy BMI, smoking
                           during pregnancy, and race;
                           paternal overweight; and
                           child gestational age, and
                           sex

Stamnes Kopp et al.        Maternal age, education,
2012, Norway (pros) [45]   exercise habit, parity,
                           prepregnancy BMI, smoking
                           during pregnancy, and
                           paternal BMI; child birth
                           weight, breastfeeding at 6
                           month, types of day care,
                           hours in screen-based
                           activities, and sex

Ehrenthal et al. 2013,     Maternal age, gestational
USA (retro) [48]           diabetes and hypertension,
                           insurance status, marital
                           status, parity,
                           preeclampsia, prepregnancy
                           BMI, diabetes,
                           hypertension, race, and
                           smoking during pregnancy;
                           child age and child born to
                           same mother

BMI = body mass index; CDC = Center for Disease Control and
Prevention; GWG = gestational weight gain; IOM = Institute of
Medicine; IOTF = International Obesity Task Force; mixed = mixed
cohort; NW = normal weight; OB = obese; OW = overweight; PCTL =
percentile; pros = prospective cohort; Ref = referent group;
retro = retrospective cohort; SES = socioeconomic status; UW =
underweight; and WHO = World Health Organization.

TABLE 2: Methodological quality assessment of included cohort
studies.
                                 Li        Oken,       Gillman
                                 et al.    et al.      et al.
                                 [38]      2007 [25]   [35]

(1) Description of background

Presented in context of          [check]    [check]    [check]
previous research, hypothesis
clearly described.

[check]: 2 elements, O: 1
element, and X: 0 element
presented

(2) Sample definition

Explicit inclusion/exclusion     [check]    [check]    [check]
criteria, uniform application
of criteria, clear description
of recruitment strategy and
participant's characteristics,
power analysis, or some other
basis noted for determining
the adequacy of study sample
size.

[check]: > 3 or more
elements, O: 2 or 3 elements,
and X: < 2 elements presented

(3) Description of gestational
weight gain

Clearly described prepregnancy   [check]       0       [check]
weight and prenatal weight.

[check]: [greater than or
equal to] 2 elements, O: 1
element, and X: 0 element
details described

(4) Description of child body
weight

Clearly defined child body       [check]    [check]    [check]
weight outcome and described
definition for
overweight/obesity.

[check]: [greater than or
equal to] 2 elements
presented, O: moderately or
very clear definition of
weight gain, and X: poor
definition of child body
weight outcome

(5) Soundness of information
on GWG.

Quality of source of                X          X          X
information on

GWG [check]:
objective measures, O:
self-report with validation,
and X: Self-report

(6) Soundness of information

Quality of source of             [check]    [check]       X
information on child body
weight outcome.

[check]: objective measures, O:
parental-reported, and X:
self-report

(7) Description on reduction
of the final sample

Adequate reporting on loss to    [check]    [check]    [check]
follow-up and the number of
participants at each stage of
study.

[check]: both elements, O: 1
element, and X: 0 elements
details described

(8) Analysis comparability

Adequately accounted for         [check]    [check]    [check]
withdrawals, lost to
follow-up, and missing data in
the analysis, appropriate
statistical methods were used
for main analysis and
adjustment of potential
confounders.

[check]: all elements clearly
presented, O: some presented,
and X: neither element present

(9) Interpretation of results

Results interpreted              [check]    [check]    [check]
appropriately based on study
design and statistics,
clinically useful, appropriate
presentation, present in the
context of prior research, and
conclusion supported by
results.

[check]: all elements clearly
present, O: any other score,
and X: conclusion not
supported by results

Overall quality

(i) High (H): [greater than or
equal to] 6 good rating
([check]) AND zero poor rating
(X)

(ii) Medium (M): < 6 good           M          M          M
ratings ([check]) OR [greater
than or equal to]6 good
ratings ([check]) and [less
than or equal to] 2 poor
ratings (X)

(iii) Low (L): [greater than
or equal to]3 poor ratings (X)
OR any other score

Notes: [check] = good; O =
fair; and X = poor.

                                 Oken,       Wrotniak   Oken,
                                 et al.      et al.     et al.
                                 2008 [41]   [47]       2009 [40]

(1) Description of background

Presented in context of           [check]    [check]     [check]
previous research, hypothesis
clearly described.

[check]: 2 elements, O: 1
element, and X: 0 element
presented

(2) Sample definition

Explicit inclusion/exclusion      [check]    [check]     [check]
criteria, uniform application
of criteria, clear description
of recruitment strategy and
participant's characteristics,
power analysis, or some other
basis noted for determining
the adequacy of study sample
size.

[check]: > 3 or more
elements,O: 2 or 3 elements,
and X: < 2 elements presented

(3) Description of gestational
weight gain

Clearly described prepregnancy    [check]    [check]        0
weight and prenatal weight.

[check]: [greater than or
equal to] 2 elements, O: 1
element, and X: 0 element
details described

(4) Description of child body
weight

Clearly defined child body        [check]    [check]     [check]
weight outcome and described
definition for
overweight/obesity.

[check]: [greater than or
equal to] 2 elements
presented, O: moderately or
very clear definition of
weight gain, and X: poor
definition of child body
weight outcome

(5) Soundness of information
on GWG.

Quality of source of                 X          X           X
information on

GWG [check]:
objective measures, O:
self-report with validation,
and X: Self-report

(6) Soundness of information

Quality of source of                 X       [check]     [check]
information on child body
weight outcome.

[check]: objective measures, O:
parental-reported, and X:
self-report

(7) Description on reduction
of the final sample

Adequate reporting on loss to     [check]    [check]     [check]
follow-up and the number of
participants at each stage of
study.

[check]: both elements, O: 1
element, and X: 0 elements
details described

(8) Analysis comparability

Adequately accounted for          [check]    [check]        0
withdrawals, lost to
follow-up, and missing data in
the analysis, appropriate
statistical methods were used
for main analysis and
adjustment of potential
confounders.

[check]: all elements clearly
presented, O: some presented,
and X: neither element present

(9) Interpretation of results

Results interpreted               [check]    [check]        0
appropriately based on study
design and statistics,
clinically useful, appropriate
presentation, present in the
context of prior research, and
conclusion supported by
results.

[check]: all elements clearly
present, O: any other score,
and X: conclusion not
supported by results

Overall quality

(i) High (H): [greater than or
equal to] 6 good rating
([check]) AND zero poor rating
(X)

(ii) Medium (M): < 6 good            M          M           M
ratings ([check]) OR [greater
than or equal to]6 good
ratings ([check]) and [less
than or equal to] 2 poor
ratings (X)

(iii) Low (L): [greater than
or equal to]3 poor ratings (X)
OR any other score

Notes: [check] = good; O =
fair; and X = poor.

                                 Olson      Steube    Fraser
                                 et al.     et al.    et al.
                                 [42, 50]   [46]      [23]

(1) Description of background

Presented in context of          [check]    [check]   [check]
previous research, hypothesis
clearly described.

[check]: 2 elements, O: 1
element, and X: 0 element
presented

(2) Sample definition

Explicit inclusion/exclusion     [check]    [check]   [check]
criteria, uniform application
of criteria, clear description
of recruitment strategy and
participant's characteristics,
power analysis, or some other
basis noted for determining
the adequacy of study sample
size.

[check]: > 3 or more
elements, O: 2 or 3 elements,
and X: < 2 elements presented

(3) Description of gestational
weight gain

Clearly described prepregnancy      0          X      [check]
weight and prenatal weight.

[check]: [greater than or
equal to] 2 elements, O: 1
element, and X: 0 element
details described

(4) Description of child body
weight

Clearly defined child body       [check]    [check]   [check]
weight outcome and described
definition for
overweight/obesity.

[check]: [greater than or
equal to] 2 elements
presented, O: moderately or
very clear definition of
weight gain, and X: poor
definition of child body
weight outcome

(5) Soundness of information
on GWG.

Quality of source of             [check]       0         X
information on

GWG [check]:
objective measures, O:
self-report with validation,
and X: Self-report

(6) Soundness of information

Quality of source of                X       [check]   [check]
information on child body
weight outcome.

[check]: objective measures, O:
parental-reported, and X:
self-report

(7) Description on reduction
of the final sample

Adequate reporting on loss to    [check]    [check]   [check]
follow-up and the number of
participants at each stage of
study.

[check]: both elements, O: 1
element, and X: 0 elements
details described

(8) Analysis comparability

Adequately accounted for         [check]    [check]   [check]
withdrawals, lost to
follow-up, and missing data in
the analysis, appropriate
statistical methods were used
for main analysis and
adjustment of potential
confounders.

[check]: all elements clearly
presented, O: some presented,
and X: neither element present

(9) Interpretation of results

Results interpreted              [check]    [check]   [check]
appropriately based on study
design and statistics,
clinically useful, appropriate
presentation, present in the
context of prior research, and
conclusion supported by
results.

[check]: all elements clearly
present, O: any other score,
and X: conclusion not
supported by results

Overall quality

(i) High (H): [greater than or
equal to] 6 good rating
([check]) AND zero poor rating
(X)

(ii) Medium (M): < 6 good           M          M         M
ratings ([check]) OR [greater
than or equal to]6 good
ratings ([check]) and [less
than or equal to] 2 poor
ratings (X)

(iii) Low (L): [greater than
or equal to]3 poor ratings (X)
OR any other score

Notes: [check] = good; O =
fair; and X = poor.

                                 Magerison   Schack-    Andersen
                                 Zilko       Nielsen    et al.
                                 et al.      et al.     [32]
                                 [31]        [44]

(1) Description of background

Presented in context of           [check]    [check]    [check]
previous research, hypothesis
clearly described.

[check]: 2 elements, O: 1
element, and X: 0 element
presented

(2) Sample definition

Explicit inclusion/exclusion      [check]    [check]    [check]
criteria, uniform application
of criteria, clear description
of recruitment strategy and
participant's characteristics,
power analysis, or some other
basis noted for determining
the adequacy of study sample
size.

[check]: > 3 or more
elements, O: 2 or 3 elements,
and X: < 2 elements presented

(3) Description of gestational
weight gain

Clearly described prepregnancy    [check]       0       [check]
weight and prenatal weight.

[check]: [greater than or
equal to] 2 elements, O: 1
element, and X: 0 element
details described

(4) Description of child body
weight

Clearly defined child body        [check]    [check]    [check]
weight outcome and described
definition for
overweight/obesity.

[check]: [greater than or
equal to] 2 elements
presented, O: moderately or
very clear definition of
weight gain, and X: poor
definition of child body
weight outcome

(5) Soundness of information
on GWG.

Quality of source of                 X          X       [check]
information on

GWG [check]:
objective measures, O:
self-report with validation,
and X: Self-report

(6) Soundness of information

Quality of source of                 0       [check]       0
information on child body
weight outcome.

[check]: objective measures, O:
parental-reported, and X:
self-report

(7) Description on reduction
of the final sample

Adequate reporting on loss to     [check]    [check]    [check]
follow-up and the number of
participants at each stage of
study.

[check]: both elements, O: 1
element, and X: 0 elements
details described

(8) Analysis comparability

Adequately accounted for          [check]    [check]    [check]
withdrawals, lost to
follow-up, and missing data in
the analysis, appropriate
statistical methods were used
for main analysis and
adjustment of potential
confounders.

[check]: all elements clearly
presented, O: some presented,
and X: neither element present

(9) Interpretation of results

Results interpreted               [check]    [check]    [check]
appropriately based on study
design and statistics,
clinically useful, appropriate
presentation, present in the
context of prior research, and
conclusion supported by
results.

[check]: all elements clearly
present, O: any other score,
and X: conclusion not
supported by results

Overall quality

(i) High (H): [greater than or
equal to] 6 good rating
([check]) AND zero poor rating
(X)

(ii) Medium (M): < 6 good            M          M          M
ratings ([check]) OR [greater
than or equal to]6 good
ratings ([check]) and [less
than or equal to] 2 poor
ratings (X)

(iii) Low (L): [greater than
or equal to]3 poor ratings (X)
OR any other score

Notes: [check] = good; O =
fair; and X = poor.

                                 Branum    Lawlor    Rooney
                                 et al.    et al.    et al.
                                 [33]      [37]      [43]

(1) Description of background

Presented in context of          [check]   [check]   [check]
previous research, hypothesis
clearly described.

[check]: 2 elements, O: 1
element, and X: 0 element
presented

(2) Sample definition

Explicit inclusion/exclusion     [check]   [check]   [check]
criteria, uniform application
of criteria, clear description
of recruitment strategy and
participant's characteristics,
power analysis, or some other
basis noted for determining
the adequacy of study sample
size.

[check]: > 3 or more
elements, O: 2 or 3 elements,
and X: < 2 elements presented

(3) Description of gestational
weight gain

Clearly described prepregnancy      0      [check]   [check]
weight and prenatal weight.

[check]: [greater than or
equal to] 2 elements, O: 1
element, and X: 0 element
details described

(4) Description of child body
weight

Clearly defined child body       [check]   [check]   [check]
weight outcome and described
definition for
overweight/obesity.

[check]: [greater than or
equal to] 2 elements
presented, O: moderately or
very clear definition of
weight gain, and X: poor
definition of child body
weight outcome

(5) Soundness of information
on GWG.

Quality of source of                X         X         X
information on

GWG [check]:
objective measures, O:
self-reportwith validation,
and X: Self-report

(6) Soundness of information

Quality of source of             [check]   [check]   [check]
information on child body
weight outcome.

[check]: objective measures, O:
parental-reported, and X:
self-report

(7) Description on reduction
of the final sample

Adequate reporting on loss to    [check]   [check]   [check]
follow-up and the number of
participants at each stage of
study.

[check]: both elements, O: 1
element, and X: 0 elements
details described

(8) Analysis comparability

Adequately accounted for         [check]   [check]   [check]
withdrawals, lost to
follow-up, and missing data in
the analysis, appropriate
statistical methods were used
for main analysis and
adjustment of potential
confounders.

[check]: all elements clearly
presented, O: some presented,
and X: neither element present

(9) Interpretation of results

Results interpreted              [check]   [check]   [check]
appropriately based on study
design and statistics,
clinically useful, appropriate
presentation, present in the
context of prior research, and
conclusion supported by
results.

[check]: all elements clearly
present, O: any other score,
and X: conclusion not
supported by results

Overall quality

(i) High (H): [greater than or
equal to] 6 good rating
([check]) AND zero poor rating
(X)

(ii) Medium (M): < 6 good           M         M         M
ratings ([check]) OR [greater
than or equal to]6 good
ratings ([check]) and [less
than or equal to] 2 poor
ratings (X)

(iii) Low (L): [greater than
or equal to]3 poor ratings (X)
OR any other score

Notes: [check] = good; O =
fair; and X = poor.

                                 Ensenauer   Elinkle   Laitinen
                                 et al.      et al.    et al.
                                 [34]        [36]      [24]

(1) Description of background

Presented in context of           [check]    [check]   [check]
previous research, hypothesis
clearly described.

[check]: 2 elements, O: 1
element, and X: 0 element
presented

(2) Sample definition

Explicit inclusion/exclusion      [check]    [check]   [check]
criteria, uniform application
of criteria, clear description
of recruitment strategy and
participant's characteristics,
power analysis, or some other
basis noted for determining
the adequacy of study sample
size.

[check]: > 3 or more
elements, O: 2 or 3 elements,
and X: < 2 elements presented

(3) Description of gestational
weight gain

Clearly described prepregnancy    [check]    [check]   [check]
weight and prenatal weight.

[check]: [greater than or
equal to] 2 elements, O: 1
element, and X: 0 element
details described

(4) Description of child body
weight

Clearly defined child body        [check]    [check]   [check]
weight outcome and described
definition for
overweight/obesity.

[check]: [greater than or
equal to] 2 elements
presented, O: moderately or
very clear definition of
weight gain, and X: poor
definition of child body
weight outcome

(5) Soundness of information
on GWG.

Quality of source of                 X          X         X
information on

GWG [check]:
objective measures, O:
self-report with validation,
and X: Self-report

(6) Soundness of information

Quality of source of              [check]    [check]   [check]
information on child body
weight outcome.

[check]: objective measures, O:
parental-reported, and X:
self-report

(7) Description on reduction
of the final sample

Adequate reporting on loss to     [check]    [check]   [check]
follow-up and the number of
participants at each stage of
study.

[check]: both elements, O: 1
element, and X: 0 elements
details described

(8) Analysis comparability

Adequately accounted for          [check]    [check]   [check]
withdrawals, lost to
follow-up, and missing data in
the analysis, appropriate
statistical methods were used
for main analysis and
adjustment of potential
confounders.

[check]: all elements clearly
presented, O: some presented,
and X: neither element present

(9) Interpretation of results

Results interpreted               [check]    [check]   [check]
appropriately based on study
design and statistics,
clinically useful, appropriate
presentation, present in the
context of prior research, and
conclusion supported by
results.

[check]: all elements clearly
present, O: any other score,
and X: conclusion not
supported by results

Overall quality

(i) High (H): [greater than or
equal to] 6 good rating
([check]) AND zero poor rating
(X)

(ii) Medium (M): < 6 good            M          M         M
ratings ([check]) OR [greater
than or equal to]6 good
ratings ([check]) and [less
than or equal to] 2 poor
ratings (X)

(iii) Low (L): [greater than
or equal to]3 poor ratings (X)
OR any other score

Notes: [check] = good; O =
fair; and X = poor.

                                 Lindberg  Magerison-  Stamens-
                                 et al.    Zilko       Kopp
                                 [49]      et al.      et al.
                                           [39]        [45]

(1) Description of background

Presented in context of          [check]    [check]    [check]
previous research, hypothesis
clearly described.

[check]: 2 elements, O: 1
element, and X: 0 element
presented

(2) Sample definition

Explicit inclusion/exclusion     [check]    [check]    [check]
criteria, uniform application
of criteria, clear description
of recruitment strategy and
participant's characteristics,
power analysis, or some other
basis noted for determining
the adequacy of study sample
size.

[check]: > 3 or more
elements, O: 2 or 3 elements,
and X: < 2 elements presented

(3) Description of gestational
weight gain

Clearly described prepregnancy      X          0          X
weight and prenatal weight.

[check]: [greater than or
equal to] 2 elements, O: 1
element, and X: 0 element
details described

(4) Description of child body
weight

Clearly defined child body       [check]    [check]    [check]
weight outcome and described
definition for
overweight/obesity.

[check]: [greater than or
equal to] 2 elements
presented, O: moderately or
very clear definition of
weight gain, and X: poor
definition of child body
weight outcome

(5) Soundness of information
on GWG.

Quality of source of                X          X          X
information on

GWG [check]:
objective measures, O:
self-report with validation,
and X: Self-report

(6) Soundness of information

Quality of source of             [check]    [check]       0
information on child body
weight outcome.

[check]: objective measures, O:
parental-reported, and X:
self-report

(7) Description on reduction
of the final sample

Adequate reporting on loss to    [check]    [check]    [check]
follow-up and the number of
participants at each stage of
study.

[check]: both elements, O: 1
element, and X: 0 elements
details described

(8) Analysis comparability

Adequately accounted for         [check]    [check]    [check]
withdrawals, lost to
follow-up, and missing data in
the analysis, appropriate
statistical methods were used
for main analysis and
adjustment of potential
confounders.

[check]: all elements clearly
presented, O: some presented,
and X: neither element present

(9) Interpretation of results

Results interpreted              [check]    [check]    [check]
appropriately based on study
design and statistics,
clinically useful, appropriate
presentation, present in the
context of prior research, and
conclusion supported by
results.

[check]: all elements clearly
present, O: any other score,
and X: conclusion not
supported by results

Overall quality

(i) High (H): [greater than or
equal to] 6 good rating
([check]) AND zero poor rating
(X)

(ii) Medium (M): < 6 good           M          M          M
ratings ([check]) OR [greater
than or equal to]6 good
ratings ([check]) and [less
than or equal to] 2 poor
ratings (X)

(iii) Low (L): [greater than
or equal to]3 poor ratings (X)
OR any other score

Notes: [check] = good; O =
fair; and X = poor.

                                 Ehrenthal
                                 et al.
                                 [48]

(1) Description of background

Presented in context of           [check]
previous research, hypothesis
clearly described.

[check]: 2 elements, O: 1
element, and X: 0 element
presented

(2) Sample definition

Explicit inclusion/exclusion      [check]
criteria, uniform application
of criteria, clear description
of recruitment strategy and
participant's characteristics,
power analysis, or some other
basis noted for determining
the adequacy of study sample
size.

[check]: > 3 or more
elements, O: 2 or 3 elements,
and X: < 2 elements presented

(3) Description of gestational
weight gain

Clearly described prepregnancy    [check]
weight and prenatal weight.

[check]: [greater than or
equal to] 2 elements, O: 1
element, and X: 0 element
details described

(4) Description of child body
weight

Clearly defined child body        [check]
weight outcome and described
definition for
overweight/obesity.

[check]: [greater than or
equal to] 2 elements
presented, O: moderately or
very clear definition of
weight gain, and X: poor
definition of child body
weight outcome

(5) Soundness of information
on GWG.

Quality of source of                 0
information on

GWG [check]:
objective measures, O:
self-report with validation,
and X: Self-report

(6) Soundness of information

Quality of source of              [check]
information on child body
weight outcome.

[check]: objective measures, O:
parental-reported, and X:
self-report

(7) Description on reduction
of the final sample

Adequate reporting on loss to     [check]
follow-up and the number of
participants at each stage of
study.

[check]: both elements, O: 1
element, and X: 0 elements
details described

(8) Analysis comparability

Adequately accounted for          [check]
withdrawals, lost to
follow-up, and missing data in
the analysis, appropriate
statistical methods were used
for main analysis and
adjustment of potential
confounders.

[check]: all elements clearly
presented, O: some presented,
and X: neither element present

(9) Interpretation of results

Results interpreted               [check]
appropriately based on study
design and statistics,
clinically useful, appropriate
presentation, present in the
context of prior research, and
conclusion supported by
results.

[check]: all elements clearly
present, O: any other score,
and X: conclusion not
supported by results

Overall quality

(i) High (H): [greater than or
equal to] 6 good rating
([check]) AND zero poor rating
(X)

(ii) Medium (M): < 6 good            M
ratings ([check]) OR [greater
than or equal to]6 good
ratings ([check]) and [less
than or equal to] 2 poor
ratings (X)

(iii) Low (L): [greater than
or equal to]3 poor ratings (X)
OR any other score

Notes: [check] = good; O =
fair; and X = poor.

TABLE 3: Summary of the association between maternal GWG and
offspring body weight outcomes.

Study                      Child   Child BMI z-score
                            age    Beta coefficient
Total GWG (#)
  Oken et al. 2007           3     0.06 (0.05, 0.07)
    [25]
  Branum et al. 2011         4     Within-family: -0.03
    [33]                           (-0.08, 0.02)
  Ensenauer et al. 2013     5.8    Between-family: 0.01
    [34]                           (-0.02, 0.04)
  Magerison-Zilko et al.     5     0.02 (0.01, 0.03)
    2012 [39]
  Andersen et al. 2011       7     0.04 (0.03, 0.06)
    [32] (a)
  Wrotniak et al. 2008       7
    [47]
  Schack-Nielsen et al.    1-14    0.01 to 0.03 (NA)
    2010 [44]
  Oken et al. 2008         9-14    0.006 (0.005, 0.007)
    [41]
Net GWG
  Olson et al. 2009          3
    [42, 50]
  Oken et al. 2007 [25]      3     0.02 (0.01, 0.03)
  Ehrenthal et al. 2013      4     0.012 (0.006, 0.017)
    [48]
Rate of GWG
  Magerison-Zilko et al.     5
    2012 [39] (b)
  Andersen et al. 2011       7     Early: 0.05 (0.03, 0.07)
    [32] (c)                       Mid: 0.06 (0.04, 0.08)
                                   Late: 0.016
                                   (-0.002, 0.03)
                                   Early/low rate: 0.17
                                   (-0.20, 0.53)
                                   Early/medium rate: 0.33
                                   (0.11, 0.55)
                                   Early/high rate: 0.62
                                   (0.24, 1.01)
  Fraser et al. 2010         9     Mid/low rate: -0.54
    [23] (d,e)                     (2.06, 0.99)
                                   Mid/medium rate: 0.39
                                   (-0.07, 0.84)
                                   Mid/high rate: 0.62
                                   (0.26, 0.99)
                                   Late/low rate: 0.091
                                   (-0.35, 0.53)
                                   Late/medium rate: -0.031
                                   (-0.48, 0.42)
                                   Late/high rate: 0.17
                                   (-0.13, 0.46)
Excessive GWG
([paragraph])
  Branum et al. 2011         4     Within-family: 0.01
    [33]                           (-0.13, 0.14)
                                   Between-family: 0.01
                                   (-0.08, 0.10)
  Ehrenthal et al. 2013      4     0.051 (-0.039, 0.140)
    [48]
  Ensenauer et al. 2013     5.8
    [34]
  Wrotniak et al. 2008       7
    [47]
  Fraser et al. 2010         9     0.64 (0.55, 0.94)
    [23]
  Magerison Zilko et al.   2-20
    2010 [31]
  Oken et al. 2008         9-14    0.14 (0.09, 0.18)
    [41]
  Rooney et al. 2011       9-14
    [43]
Inadequate GWG
  Branum et al. 2011         4     Within-family: 0.08
    [33]                           (0.00, 0.16)
                                   Between-family: 0.04
                                   (-0.02, 0.10)
  Ehrenthal et al. 2013      4     -0.190 (-0.319, -0.062)
  Ensenauer et al. 2013     5.8
    [34]
  Wrotniak et al. 2008       7
    [47]
  Fraser et al. 2010         9     -0.21 (-0.40, -0.03)
    [23]
  Magerison Zilko et al.   2-20
    2010 [31]
  Oken et al. 2008         9-14    -0.06 (-0.10, -0.01)
    [41]
  Rooney et al. 2011       9-14
    [43]

Study                         Child OW/OB status
                              ARR or AOR
Total GWG (#)
  Oken et al. 2007            OW: 1.23 (1.16, 1.30)
    [25]
  Branum et al. 2011
    [33]
  Ensenauer et al. 2013       OW: 1.04 (1.02,1.05)
    [34]
  Magerison-Zilko et al.      OW: 1.04 (1.02,1.07)
    2012 [39]
  Andersen et al. 2011
    [32] (a)
  Wrotniak et al. 2008        OW: 1.03 (1.01, 1.05)
    [47]
  Schack-Nielsen et al.
    2010 [44]
  Oken et al. 2008            OW: 1.05 (1.04, 1.05)
    [41]
                              OB: 1.08 (1.07, 1.08)
Net GWG
  Olson et al. 2009           OW: 1.001 (NS)
    [42, 50]                  OB: 1.010 (NS)
  Oken et al. 2007 [25]
  Ehrenthal et al. 2013
    [48]
Rate of GWG
  Magerison-Zilko et al.      OW:
    2012 [39] (b)             Early: 1.05 (1.02, 1.09)
                              Mid: 1.03 (0.98, 1.08)
                              Late: 1.03 (0.98, 1.08)
  Andersen et al. 2011        OW: Early/low rate: 1.06
    [32] (c)                  (0.77,1.47)
                              Early/medium rate: 1.14
                              (0.92, 1.42)
                              Early/high rate: 1.57
                              (1.13, 2.18)

  Fraser et al. 2010           Mid/low rate: 1.05
    [23] (d,e)                (0.28, 4.00)
                              Mid/medium rate: 0.98
                              (0.62, 1.54)
                              Mid/high rate: 2.00
                              (1.43, 2.79)
                              Late/low rate: 0.88
                              (0.57,1.36)
                              Late/medium rate: 1.02
                              (0.64, 1.61)
                              Late/high rate: 1.06
                              (0.81, 1.39)
Excessive GWG
([paragraph])

  Branum et al. 2011
    [33]

  Ehrenthal et al. 2013
    [48]
  Ensenauer et al. 2013       OW: 1.57 (1.30, 1.91)
    [34]
  Wrotniak et al. 2008        OW: 1.40 (1.00, 1.95)
    [47]
  Fraser et al. 2010
    [23]
  Magerison Zilko et al.      OW: 1.27 (1.10, 1.48)
    2010 [31]
  Oken et al. 2008            OW: 1.27 (1.12,1.44)
    [41]
                              OB: 1.42 (1.19, 1.70)
  Rooney et al. 2011          OB: 1.73 (1.06, 2.80)
    [43]
Inadequate GWG
  Branum et al. 2011
    [33]

  Ehrenthal et al. 2013
  Ensenauer et al. 2013       OW: 1.20 (0.91, 1.57)
    [34]
  Wrotniak et al. 2008        OW: 0.93 (0.72, 1.21)
    [47]
  Fraser et al. 2010
    [23]
  Magerison Zilko et al.      OW: 0.90 (NS)
    2010 [31]
  Oken et al. 2008            OW: 0.97 (1.19, 1.70)
    [41]                      OB: 0.91 (0.74, 1.13)
  Rooney et al. 2011          OB: 0.77 (0.45,1.34)
    [43]

(a) log transformed value.

(b) Rate of GWG expressed as change in kilograms per trimester.
Early: 1st trimester, mid: 2nd trimester, and late: 3rd
trimester.

(c) Rate of GWG expressed as change in grams per week. Early: until
interview 1 (12-20 weeks of gestation), mid: between interview 1
and interview 2 (25-32 weeks of gestation), and late: between
interview 2 and delivery.

(d) Rate of GWG expressed as change in grams per week. Early: 0-14
weeks of gestation, mid: > 14-35 weeks of gestation, and late: >
36 weeks of gestation; low rate: [less than or equal to] 0 g in
0-14 weeks of gestation, [less than or equal to] 250 g per week
in other GWG periods, medium rate: 0-500 g in 0-14 weeks of
gestation, 250-500 g in other GWG periods, and high rate: > 500 g
for all GWG period.

(e) BMI (kg/[m.sup.2]) was used as the outcome.

(#) Only studies that used total GWG as continuous variables and
presented full sample analyses are included.

([paragraph]) Only studies that used adequate GWG as the referent
group are included.

ARR = adjusted relative risk, AOR = adjusted odd ratio,
GWG = gestational weight gain, NA = not available, NS = not
significant, OW = overweight, and OB = obesity.

TABLE 4: Summary of the association between maternal GWG and
offspring's body weight outcomes stratified by maternal
prepregnancy BMI.

Study                       Child   Child BMI c-score, B coefficient
                                              (95% Cl)

                             age         UW                NW
Total GWG
  Oken et al. 2007 [25]       3                     0.02 (0.02, 0.06)
  Hinkle et al. 2012 [36]     5     -0.06           0.02 (0.00, 0.04)
                                    (-0.16, 0.03)
  Ensenauer et al. 2013      5.8
    [34]
  Wrotniak et al. 2008        7
    [47]
  Magerison Zilko et al.    2-20
   2010 [31]
Net GWG
  Lawlor et al. 2011         18                      Within-family:
    [37] (a)                                              0.01
                                                      (-0.02, 0.02)
                                                     Between-family:
                                                          0.07
                                                      (0.06, 0.07)
Rate of GWG
  Oken et al. 2009            3
    [40] (b)
Excessive GWG
  Ensenauer et al. 2013      5.8
    [34]
  Wrotniak et al. 2008        7
    [47]
Inadequate GWG
  Ensenauer et al. 2013      5.8
    [34]
  Wrotniak et al. 2008        7
    [47]

Study                       Child BMI c-score, B coefficient (95% Cl)

                                    OW                   OB
Total GWG
  Oken et al. 2007 [25]     0.03 (0.02, 0.04)
  Hinkle et al. 2012 [36]   0.02 (-0.01, 0.06)   0.00 (-0.04, 0.03)
  Ensenauer et al. 2013
    [34]
  Wrotniak et al. 2008
    [47]
  Magerison Zilko et al.
   2010 [31]
Net GWG
  Lawlor et al. 2011          Within-family:
    [37] (a)                       0.06
                               (0.01, 0.02)
                             Between-family:
                                   0.02
                               (0.01, 0.03)
Rate of GWG
  Oken et al. 2009
    [40] (b)
Excessive GWG
  Ensenauer et al. 2013
    [34]
  Wrotniak et al. 2008
    [47]
Inadequate GWG
  Ensenauer et al. 2013
    [34]
  Wrotniak et al. 2008
    [47]

Study                       Child OW/OB status, AOR/ARR (95% Cl)

                                   UW                 NW
Total GWG
  Oken et al. 2007 [25]
  Hinkle et al. 2012 [36]

  Ensenauer et al. 2013     1.03 (0.90,1.16)   1.04 (1.02,1.07)
    [34]
  Wrotniak et al. 2008                         1.07 (0.99,1.15)
    [47]
  Magerison Zilko et al.    1.02 (0.99,1.05)   1.03 (1.02,1.04)
   2010 [31]
Net GWG
  Lawlor et al. 2011
    [37] (a)
Rate of GWG
  Oken et al. 2009                             1.16 (0.88,1.51)
    [40] (b)
Excessive GWG
  Ensenauer et al. 2013     1.50 (0.36, 6.39)  1.29 (1.01,1.66)
    [34]
  Wrotniak et al. 2008                         3.26 (0.95,11.16)
    [47]
Inadequate GWG
  Ensenauer et al. 2013     1.74 (0.30, 8.97)  1.02 (0.71,1.43)
    [34]
  Wrotniak et al. 2008                         0.55 (0.22,1.21)
    [47]

Study                       Child OW/OB status, AOR/ARR (95% Cl)

                                   OW                  OB
Total GWG
  Oken et al. 2007 [25]
  Hinkle et al. 2012 [36]
  Ensenauer et al. 2013     1.01 (0.98,1.04)    1.04 (1.01,1.07)
    [34]
  Wrotniak et al. 2008      1.01 (0.99,1.03)
    [47]
  Magerison Zilko et al.    1.02 (1.00,1.04)    1.02 (1.00,1.04)
   2010 [31]
Net GWG
  Lawlor et al. 2011
    [37] (a)
Rate of GWG
  Oken et al. 2009          1.35 (1.01,1.81)    1.22 (0.96,1.56)
    [40] (b)
Excessive GWG
  Ensenauer et al. 2013     1.64 (1.06, 2.63)   1.17 (0.70, 2.01)
    [34]
  Wrotniak et al. 2008      1.48 (1.05, 2.08)
    [47]
Inadequate GWG
  Ensenauer et al. 2013     2.52 (1.28, 4.91)   0.63 (0.30,1.30)
    [34]
  Wrotniak et al. 2008      0.95 (0.73,1.24)
    [47]

(a) BMI (kg/[m.sup.2]) was used as the outcome.

(b) Rate of GWG expressed as change per 0.1 kg per week.

GWG = gestational weight gain, UW = underweight, NW = normal
weight, OW = overweight, OB = obesity, 95%, and CI = 95%
confidence interval.
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Author:Lau, Erica Y.; Liu, Junxiu; Archer, Edward; McDonald, Samantha M.; Liu, Jihong
Publication:Journal of Obesity
Article Type:Report
Geographic Code:1USA
Date:Jan 1, 2014
Words:14637
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