Printer Friendly

THE RELATIONSHIP BETWEEN BARRIERS TO BIRTH CONTROL USE AND ACTUAL BIRTH CONTROL USE AMONG MEXICAN-AMERICAN ADOLESCENTS.

ABSTRACT

This study examined the relationship between barriers to using birth control and actual use of birth control among a national sample of Mexican-American adolescents. Participants were either over age 15 or sexually active (regardless of age). They responded to survey items on birth control use. Chi-square analysis and t tests were used to investigate whether barriers to using birth control were related to actual use during first intercourse and most recent sexual intercourse. It was found that nonusers had significantly higher barrier scores compared with users of birth control. The results indicate that attitudes toward birth control are associated with actual birth control use among Mexican-American adolescents. Additionally, males and females may have distinct barriers to using birth control. It was concluded that a better understanding of the sexual attitudes and beliefs associated with birth control is needed in order to improve programs seeking to increase the use of birth control among this rapidly exp anding, high-risk population.

Between 1990 and 1993, Hispanics surpassed African-Americans as the group with the highest adolescent birthrate (Alan Guttmacher Institute, 1994). Further, the birthrate among Mexican-American adolescents is higher than that of any other Hispanic group (Centers for Disease Control, 1993; Alan Guttmacher Institute, 1994). Interestingly, Mexican-Americans have a higher rate of early childbearing, as compared with Anglos, despite having a lower rate of early sexual intercourse (Aneshensel, Fielder, & Becerra, 1990; De Anda, Becerra & Fielder, 1988).

Various explanations have been offered for the high rate of adolescent pregnancy among Hispanics, and Mexican-Americans in particular. It should first be noted that, in a national sample, 62% of Hispanic males reported being sexually active compared with 49% of Anglo males, while 53% of Hispanic females reported sexual activity compared with 49% of Anglo females (Warren, Santelli, Everett, Kann, Collins, Cassell, Morris, & Kolbe, 1998). Second, compared with non-Hispanics, Hispanics have been found to be less knowledgeable about birth control and sexually transmitted diseases, including HIV (Council on Scientific Affairs, 1991). Erickson (1998) has stated that, "compared to Anglo and African-American teens, Latina teens know less about birth control and are less likely to use birth control at first intercourse, and have lower rates of birth control use overall" (p. 129). It therefore stands to reason that sexual activity combined with ignorance about, and negative attitudes toward, birth control would contri bute to high pregnancy rates among Hispanic adolescents.

Hispanic adolescents are less likely than Anglos or African-Americans to contact health care providers for routine care, including birth control (Lieu, Newacheck, & McManus, 1993). In light of this, it is not surprising that Hispanic adolescents are less likely than Anglos and African-Americans to use birth control (Piccinino & Mosher, 1998; Mauldon & Luker, 1996; Hodges, Leavy, Swift, & Gold, 1992; Mosher & McNally, 1991; Aneshensel et al., 1989). Further, Mexican-Americans are less likely than Cubans, Puerto Ricans, and other Hispanic adolescents to use birth control (DuRant, Seymore, Pendergrast, & Beckman, 1990).

Research with adolescents has identified various barriers to birth control use. Embarrassment about purchasing birth control and overall inconvenience have been cited by adolescents as barriers to use (Murphy & Boggess, 1998; Bernard & McKeganey, 1990). An adolescent who believes that birth control methods are likely to interfere with sexual pleasure is less likely to report use (Murphy & Boggess, 1998; Joffe & Radius, 1993; Pleck, Sonenstein, & Ku, 1993; Skurnick, Johnson, Quinones, Foster, & Louria, 1991). Communication issues between partners (Landry & Forrest, 1995), positive or ambivalent feelings about having a baby (Stevens-Simon, Singer, & Cox, 1996), male ambivalence toward the consistent use of condoms, and perception of stigma in obtaining and carrying condoms among females (Price, 1997) have also been found to be influential.

There is extensive literature focusing on adolescents' barriers to using various methods of birth control, especially condoms. Although some of these studies have included Hispanic adolescents when assessing barriers to birth control use, few have focused on Mexican-Americans. It is a common practice to lump all Hispanic subjects into one category for purposes of analysis (e.g., due to small sample sizes or because of convenience). However, this ignores cultural issues that differentiate Mexican-American adolescents from other Hispanics, and certainly from the majority population. In fact, Mexican-Americans may be at increased risk for adverse economic and social outcomes, and consequently for adolescent pregnancy. For example, a high percentage of Mexican-Americans under 18 years of age live in poverty (United States Bureau of the Census, 1991), and a higher percentage are uninsured compared with Puerto Ricans, Cubans, African-Americans, and Anglos (Trevino, Moyer, Valdez, & Stroup-Benham, 1991).

The present study utilized a national sample of 289 Mexican-American adolescents in an attempt to improve our understanding of the obstacles to their use of birth control. Participants who reported using birth control at first intercourse and at most recent intercourse were compared with those who did not. Specific barriers to birth control use were then examined to determine whether there were gender differences.

METHOD

Subjects and Data Collection

The National Longitudinal Study of Adolescent Health was designed to identify the multiple factors that impact the health-related behaviors of adolescents. Wave 1 took place between September 1994 and April 1995. A sample of 80 schools was selected from all high schools in the United States that had an 11th grade and at least 30 students (N = 26,666). The sample was stratified on the basis of region, urbanicity, school type, and ethnicity. Schools that declined to participate were replaced with demographically similar schools. Additionally, feeder schools were identified and recruited, resulting in a "pair" of schools.

Participating schools provided student rosters and set aside one 45-to 60-minute class period for administration of the questionnaire, which was completed by 90,118 of 119,233 eligible students in grades 7 through 12. Roughly 200 students were selected from each of the 80 pairs of schools (a total of 12,105 students) to take part in a 90-minute in-home interview between April and December 1995. The response rate was 79%. For the purpose of the present study, only sexually active Mexican-American adolescents (regardless of age) or those over age 15 (regardless of sexual activity) were selected for analysis (n = 289).

Measurement

There were eight items related to barriers to birth control use: (1) in general, birth control is a hassle to use; (2) birth control is too expensive; (3) using birth control is morally wrong; (4) it is/would be difficult to get a partner to use birth control with you; (5) it takes too much planning ahead of time to have birth control on hand when you are going to have sex; (6) it is difficult for you to get birth control; (7) for you, using birth control interferes/would interfere with sexual enjoyment; (8) if you used birth control, your friends might think that you were looking for sex. Response options were as follows: strongly agree (coded as 2), agree (coded as 1), neither agree nor disagree (coded as 0), disagree (coded as -1), and strongly disagree (coded as -2). Responses were combined to obtain a summative score (ranging from -16 to 16), with higher scores indicating more barriers to birth control use and lower scores indicating fewer barriers. Pearson's product-moment correlation indicated that th is barrier scale had satisfactory reliability (r = .72).

Data Analysis

Group differences in barriers to birth control use among Mexican-American males and females were examined using t tests for independent means with pooled estimates of variance for unequal group sizes. First, sexually active participants were compared with those who were not sexually active. Second, participants who reported not using birth control at most recent sexual intercourse were compared with those who did, and participants who did not use birth control at first sexual intercourse were compared with those who did. Chi-square analyses were used to examine whether individual barrier items were associated with failure to use birth control at most recent intercourse. All statistical analyses were conducted using SPSS for Windows, version 8.0 (Norusis, 1990).

RESULTS

The characteristics of the 289 Mexican-American adolescents are presented in Table 1. The majority (91%) were in grades 9 through 12. Fifty-four percent of the males and 47% of the females reported having had sexual intercourse. Of these adolescents, 50% of the males and 47% of the females reported birth control use at first intercourse. Further, 59% of the males used a birth control method at most recent sexual intercourse, while 47% of the females reported doing so.

Among both sexually active males and females, those who used birth control at first and most recent intercourse reported significantly fewer barriers to birth control use compared with those who did not use birth control (see Tables 2 and 3). In regard to birth control use at most recent intercourse, results of the chi-square analyses of individual barrier scale items (response categories were collapsed) are presented in Table 4 (females) and Table 5 (males). Among females, significant differences between those who reported birth control use at most recent sexual intercourse and those who did not were found on two items (birth control is a hassle to use; it takes too much planning ahead of time to have birth control on hand when you are going to have sex). Among males, significant differences were found on three items (it is! would be difficult to get a partner to use birth control with you; if you used birth control, your friends might think that you were looking for sex; it is difficult to get birth contro l).

DISCUSSION

This study investigated the relationship between attitudes and beliefs about birth control use and actual use among a nationally representative sample of Mexican-American adolescents. It was found that Mexican-American adolescents who did not use birth control at first and most recent sexual intercourse reported significantly more barriers to use compared with adolescents who did use birth control. Furthermore, there were gender differences in regard to particular barriers. The findings suggest that negative attitudes toward birth control deter use, consequently increasing the risk of unintended pregnancy. Thus, it is important to address both real and perceived barriers in efforts to increase the use of birth control, particularly since the delay between the start of sexual activity and consistent contraception is one of the biggest obstacles to the prevention of adolescent pregnancy (Stevens-Simon, Singer, & Cox, 1996).

The results support previous research focusing on attitudes toward birth control. Heinrich (1993) reported that, in a sample of sexually active college women, 55% perceived barriers to birth control, including fear of side effects, interference with spontaneity, and the appearance of planning for sex. Padilla and Baird (1991) reported that, of 18 sexually active Mexican-American adolescents, 78% believed that using birth control makes sex seem planned. Baird (1993) found that males were more likely than females to agree that using birth control makes sex seem planned. In the present study, females who did not use contraception at most recent sexual intercourse (versus those who did) were significantly more likely to agree that birth control is a hassle to use and takes too much planning.

The belief or experience that birth control decreases sexual pleasure is a major deterrent to its use (Murphy & Boggess, 1998; Pleck et al., 1993). This is true among both males and females (Joffe & Radius, 1993). Murphy and Boggess (1998) reported that half of their sample of adolescent males believed there was a chance they would experience less sexual pleasure with a condom. Pleck et al. (1993) found that when perceptions of reduced sexual pleasure were changed, condom use increased significantly. In the present study, males who did not use birth control at most recent sexual intercourse (versus those who did) were more likely to agree that using birth control interferes with sexual pleasure, although the difference was not statistically significant.

Males who did not use contraception at most recent intercourse (versus those who did) were more likely to agree that friends might think they were looking for sex if they used birth control. However, since sexual activity is more socially acceptable among males, it is unclear whether this survey item should be classified as a barrier or a motivator. It may, in fact, have been viewed differently by the females and males in this study.

Culturally defined attitudes toward sexuality and contraception may increase the risk of pregnancy among Mexican-American adolescents (Flares, Eyre, & Millstein, 1998). For example, marianismo refers to a female socialization pattern characterized by submission and reliance on males to make decisions, which may decrease the negotiating power of females in sexual situations (Peragallo & Mba, 1996) and contribute to low rates of birth control use and high rates of pregnancy. Whether cultural factors played a role in the findings is unknown, since acculturation was not assessed. According to Marcell (1994), a Mexican-American adolescent is as likely to be assimilated into mainstream culture as he or she is to identify with the values and traditions of previous generations with closer ties to Mexico (Marcell, 1994).

Despite the extensive literature on adolescents' birth control use, research has failed to direct sufficient attention at Hispanics, and within this overall category, Mexican-Americans. Instead, the focus, until recent years, has been on African-American and Euro-American populations (Fennelly, 1993). Yet, it may be no less true that pregnancy can have a severe social, physical, and emotional impact on a Mexican-American adolescent, contributing to lower quality of life well into adulthood. Thus, proposals such as denying Aid to Families with Dependent Children (AFDC) payments to pregnant or unwed adolescents and placing restrictions on other services, offered by lawmakers under the guise of "disincentives" (Sollum, 1995), have the potential to create a permanent underclass, which would disproportionately affect Mexican-Americans and other minorities.

There is evidence that school sexuality education programs have succeeded at altering attitudes by increasing knowledge. Unfortunately, changes in sexual behaviors (i.e., increased use of birth control) as a result of these programs are not always easy to demonstrate (Office of Technology Assessment, 1992). Nevertheless, according to data from the National Survey for Family Growth, adolescent females who participated in a formal birth control education program were 33% more likely to use birth control at first intercourse. Mauldon and Luker (1996) reported that birth control education in the same year that sexual activity was initiated increased the odds of using condoms by 70-80% and birth control pills by 50%. Even seemingly small effects of programs designed to increase the use of birth control are important, because contraceptive behavior tends to remain consistent over time. For example, it was found that 43% of adolescent females who were sexually active for two years reported the same contraceptive be havior at most recent intercourse; moreover, five out of six adolescents who used a birth control method at first sexual intercourse used one at most recent sexual intercourse (Mauldon, 1995).

DuRant et al. (1990) has suggested involving parents, churches, and health providers in a multilevel approach to preventing pregnancy among Hispanic adolescents. This approach was found to be effective in reducing the rate of adolescent pregnancy m a non-Hispanic population (Vincent, Clearie, & Schluchter, 1989). Witte (1997) reported that inner-city teens felt it was important for health education programs to reach children at an early age in order to combat both positive attitudes toward pregnancy and negative attitudes toward birth control.

The limitations of the present study should be noted. First, the accuracy of self-reported information can pose a serious problem. Because sexual initiation is often memorable, however, reports of birth control use at first intercourse are usually accurate (Mauldon & Luker, 1996). Second, birth control methods were not differentiated, and there may be different barriers to using condoms versus the birth control pill, for example. It is not known whether this sample of Mexican-Americans had a specific method in mind or answered the barrier items from a more generic standpoint. It is therefore difficult to make comparisons between this study, which assessed attitudes toward birth control use in general, and those assessing perceptions of specific birth control methods. Third, degree of acculturation was not measured.

Nevertheless, the present study established a relationship between barriers to birth control use and actual use at first and most recent sexual intercourse in a nationally representative sample of Mexican-American adolescents. By focusing on Mexican-Americans, the common pitfall of lumping all Hispanics together was avoided. The importance of furthering our understanding of the sexual attitudes, beliefs, and behaviors of specific Hispanic adolescent populations, particularly Mexican-Americans, cannot be understated.

Jeff Mathews, Youth Tobacco Initiative. Indianapolis. Indiana.

REFERENCES

Alan Guttmacher Institute. (1994). Sex and America's teenagers. New York: Alan Guttmacher Institute.

Aneshensel, C. S., Fielder, E., & Becerra, R. M. (1989). Fertility and fertility-related behavior among Mexican-American and non-Hispanic white female adolescents. Journal of Health and Social Behavior, 30, 56-76.

Aneshensel, C. S.,. Fielder, E., & Becerra, R. M. (1990). Onset of fertility-related events during adolescence: A prospective comparison of Mexican-American and non-Hispanic white females. American Journal of Public Health, 80, 959-963.

Baird, T. L. (1993). Mexican adolescent sexuality: Attitudes, knowledge, and sources of information. Hispanic Journal of Behavioral Sciences, 15, 402-417.

Bernard, M., & McKeganey, N. (1990). Adolescents, sex and injecting drug use: Risks for HIV infection. AIDS Care, 2, 103-116.

Centers for Disease Control. (1993). Childbearing patterns among selected racial/ethnic minority groups--United States, 1990. Morbidity and Mortality Weekly Report, 42 (May 28), 398-403.

Council on Scientific Affairs. (1991). Hispanic health in the United States. Journal of the American Medical Association, 265, 248-252.

De Anda, D., Becerra, R. M., & Fielder, P. (1988). Sexuality, pregnancy, and motherhood among Mexican-American adolescents. Journal of Adolescent Research, 3, 403-411.

DuRant, R. H., Seymore, C., Pendergrast, R., & Beckman, R. (1990). Contraceptive behavior among sexually active Hispanic adolescents. Journal of Adolescent Health Care, 11, 490-496.

Erickson, P. I. (1998). Latina adolescent childbearing in east Los Angeles. Austin: University of Texas Press.

Fennelly, K. (1993). Sexual activity and childbearing among Hispanic adolescents in the United States. In R. L. Lerner (Ed.), Early adolescence: Perspectives on research, policy, and intervention (pp. 335-352). Hillsdale, NJ: Lawrence Erlbaum Associates.

Flores, E., Eyre, S. L., & Millstein, S. G. (1998). Sociocultural beliefs related to sex among Mexican-American adolescents. Hispanic Journal of Behavioral Sciences, 20, 60-82.

Joffe, A., & Radius, S. M. (1993). Self-efficacy and intent to use condoms among entering college freshmen. Journal of Adolescent Health, 14, 262-268.

Heinrich, L. B. (1993). Birth control self-efficacy in college women. Journal of Adolescent Health, 14, 269-276.

Hodges, B. C., Leavy, J., Swift, R., & Gold, R. S. (1992). Gender and ethnic differences in adolescent attitudes towards condom use. Journal of School Health, 62, 103-106.

Landry, D. J., & Forrest, J. D. (1995). How old are U.S. fathers? Family Planning Perspectives, 27, 159-165.

Lieu, T. A., Newacheck, P. W., & McManus, M. A. (1993). Race, ethnicity, and access to ambulatory care among U.S. adolescents. American Journal of Public Health, 83, 960-965.

Marcell, A. V. (1994). Understanding ethnicity, identity formation, and risk behavior among adolescents of Mexican descent. Journal of School Health, 64, 323-327.

Mauldon, J. (1995). The effect of sexuality education on teenagers' use of birth control. Paper presented at the annual meeting of the Population Association of America, San Francisco, CA.

Mauldon, J., & Luker, K. (1996). The effects of birth control education on method used at first intercourse. Family Planning Perspectives, 28, 19-24.

Mosher, Y. D., & McNally, J. W. (1991). Birth control use at first premarital intercourse: United States, 1965-1988. Family Planning Perspectives, 23, 108-122.

Murphy, J. J., & Boggess, S. (1998). Increased condom use among teenage males, 1988-1995: The role of attitudes. Family Planning Perspectives, 30, 276-280, 303.

Norusis, M. J. (1990). SPSS advanced statistics user's guide. Chicago: SPSS Inc.

Office of Technology Assessment. (1992). Adolescent health: Volume II--Background and the effectiveness of selected prevention and treatment services. Washington, DC: U.S. Government Printing Office.

Padilla, A. M., & Baird, T. L. (1991). Mexican-American adolescent sexuality and sexual knowledge: An exploratory study. Hispanic Journal of Behavioral Sciences, 13, 95-104.

Peragallo, N. P., & Alba, M. L. (1996). HIV/AIDS: Risk factors, incidence and intervention among Latinos in the United States. In S. Torres (Ed.), Hispanic voices: Hispanic health educators speak out (pp. 126-142). New York: NLN Press.

Piccinino, L. J., & Mosher, W. D. (1998). Trends in birth control use in the US: 1982-1995. Family Planning Perspectives, 30, 4-10, 16.

Pleck, J. H., Sonenstein, F. L., & Ku, L. C. (1993). Changes in adolescent males' use of and attitudes towards condoms, 1988-1991. Family Planning Perspectives, 25, 106-109, 117.

Price, A. (1997). Culture and condoms: A review of research literature. Modern Midwife, 7, 28-31.

Skurnick, J. H., Johnson, R. L., Quinones, M. A., Foster, J. D., & Louria, D. B. (1991). New Jersey high school students' knowledge, attitudes and behavior regarding AIDS. MDS Education and Prevention, 3, 21-30.

Sollum, T. (1995). State actions on reproductive health issues in 1994. Family Planning Perspectives, 27, 83-87.

Stevens-Simon, C., Singer, D., & Cox, A. (1996). Why pregnant adolescents say they did not use birth control prior to conception. Journal of Adolescent Health, 19, 48-53.

Trevino, F. M., Moyer, U. E., Valdez, R. B., & Stroup-Benham, C. A. (1991). Health insurance coverage and utilization of health services by Mexican-Americans, mainland Puerto Ricans, and Cuban Americans. Journal of the American Medical Association, 265, 233-237.

United States Bureau of the Census. (1991). The Hispanic population in the United States: March 1991 (Current Population Reports, Series P-20, No. 455). Washington, DC: U.S. Government Printing Office.

Vincent, M. L., Clearie, A. F., & Schluchter, M.D. (1989). Reducing adolescent pregnancy through school- and community-based education. Journal of the American Medical Association, 257, 3382-3386.

Warren, C. W., Santelli, J. S., Everett, S. A, Kann, L., Collins, J. L., Cassell, C., Morris, L., & Kolbe, L. J. (1998). Sexual behavior among U.S. high school students, 1990-1995. Family Planning Perspectives, 30, 170-172, 200.

Witte, K. (1997). Preventing teen pregnancy through persuasive communications: Realities, myths, and the hard-fact truths. Journal of Community Health, 22, 137-154.
 Characteristics of the Sample (N=289)
 Males Females
 (n=151) (n=138)
 n (%) n (%)
Ever had sex
 Yes 81 (54) 64 (47)
 No 70 (46) 72 (53)
First sex - used birth control
 Yes 40 (50) 30 (47)
 No 40 (50) 34 (53)
Most recent sex - used birth control
 Yes 47 (59) 30 (47)
 No 33 (41) 34 (53)
Grade
 7th 4 (3) 3 (2)
 8th 9 (6) 9 (7)
 9th 28 (19) 27 (20)
 10th 42 (29) 36 (28)
 11th 32 (22) 32 (24)
 12th 31 (21) 26 (19)
 Missing/legitimate skip 5 5
 Differences Among Females on Barriers to
 Birth Control Scale
 n M SD df t p
Not sexually active 72 -4.3 5.5
Sexually active 64 -5.9 6.3
 134 1.6 .115
Did not use birth control
at first intercourse 34 -3.5 6.6
Used birth control
at first intercourse 29 -7.7 5.2
 61 2.8 .006
Did not use birth control
at most recent intercourse 34 -4.4 5.5
Used birth control
at most recent intercourse 30 -7.7 6.9
 61 2.2 .030
 Differences Among Males on Barriers to Birth
 Control Scale
 n M SD df t p
Not sexually active 65 -4.6 4.9
Sexually active 78 -3.9 6.3
 141 .74 .462
Did not use birth control
at first intercourse 39 -2.0 5.1
Used birth control
at first intercourse 38 -6.1 6.8
 75 3.0 .004
Did not use birth control
at most recent intercourse 32 -1.9 5.3
Used birth control
at most recent intercourse 45 -5.5 6.5
 75 2.6 .011
 Birth Control Use at Most Recent
 Sexual Intercourse
 by Barrier Scale Items (Females)
Barrier Used Did Not Use
Scale (n=30) (n=34)
Items % % p
Difficult to get partner to use birth control
 Agree or neutral 20 35
 Disagree 80 65
 .265
Feel birth control interferes with pleasure
 Agree or neutral 27 39
 Disagree 73 61
 .423
Friends might think you were looking for sex
 Agree or neutral 23 39
 Disagree 77 61
 .189
It is difficult to get birth control
 Agree or neutral 27 39
 Disagree 73 61
 .423
Using birth control is morally wrong
 Agree or neutral 37 47
 Disagree 63 53
 .454
Birth control is too expensive
 Agree or neutral 30 38
 Disagree 70 62
 .600
Birth control is a hassle to use
 Agree or neutral 30 38
 Disagree 70 62
 .011
Birth control involves too much planning
 Agree or neutral 10 38
 Disagree 90 62
 .012
 Birth Control Use at Most Recent
 Sexual Intercourse by Barrier Scale
 Items (Males)
Barrier Used Did not Use
Scale (n=47) (n=33)
Items % % P
Difficult to get partner to
use birth control
 Agree or neutral 37 63
 Disagree 63 38
 .038
Feel birth control interferes with pleasure
 Agree or neutral 40 45
 Disagree 60 55
 .650
Friends might think you were looking for sex
 Agree or neutral 41 73
 Disagree 59 27
 .007
It is difficult to get birth control
 Agree or neutral 33 73
 Disagree 67 27
 .001
Using birth control is morally wrong
 Agree or neutral 50 67
 Disagree 50 33
 .171
Birth control is too expensive
 Agree or neutral 28 34
 Disagree 72 66
 .623
Birth control is a hassle to use
 Agree or neutral 28 42
 Disagree 72 58
 .233
Birth control involves too much planning
 Agree or neutral 63 65
 Disagree 37 35
 1.0
COPYRIGHT 2000 Libra Publishers, Inc.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2000 Gale, Cengage Learning. All rights reserved.

Article Details
Printer friendly Cite/link Email Feedback
Author:Pesa, Jacqueline A.; Mathews, Jeff
Publication:Adolescence
Geographic Code:1USA
Date:Dec 22, 2000
Words:4194
Previous Article:PUNISHMENTS ADOLESCENTS FIND JUSTIFIED: AN EXAMINATION OF ATTITUDES TOWARD DELINQUENCY.
Next Article:KNOWLEDGE ABOUT THE DELETERIOUS EFFECTS OF SMOKING AND ITS RELATIONSHIP TO SMOKING CESSATION AMONG PREGNANT ADOLESCENTS.
Topics:

Terms of use | Copyright © 2017 Farlex, Inc. | Feedback | For webmasters