Meconium-stained amniotic fluid and meconium aspiration syndrome--a study on risk factors and neonatal outcome.
Meconium is a sterile, thick, black green, odourless material that results from the accumulation of debris in the foetal intestine during the third month of gestation.  At times this can be passed before the baby is born, discolouring the amniotic fluid.  Meconium is passed following an asphyxial episode in utero.
If the asphyxia episode is accompanied by prolonged gasping, meconium will be drawn deeply in to the lungs.  The passage of meconium into the amniotic fluid during labour is one of the traditional indicators of foetal distress which is associated with increased perinatal morbidity and mortality. 
Infants born through Meconium-stained amniotic fluid (MSAF) are more likely to develop respiratory distress compared to their counterparts born through clear amniotic fluid . MSAF occurs in about 7-22% of live births. There are contradictory studies about the effect of MSAF on the obstetric outcome. 
Meconium aspiration syndrome (MAS) is a serious and potentially preventable condition occurring usually in term and post-term babies.  MAS is one of the most common causes of respiratory distress in term and post-term infants, which remains a major objective for obstetricians and neonatologists. 
According to National Neonatal Perinatal Database (NNPD), MAS was defined as Presence of Two of the following
a) Meconium staining of liquor or staining of nails or umbilical cord or skin.
b) Respiratory distress within one hour of birth.
c) Radiological evidence of aspiration pneumonitis (Atelectasis and/or hyperinflation).
d) Clinically MAS is usually defined as a respiratory dysfunction in an infant who is born with MSAF (i.e., visual observation of greenish fluid discolouration) and shows symptoms that cannot be otherwise explained.
Risk factors that may cause foetal distress which leads to MSAF include placental ageing due to post-dated pregnancy, IUGR, oligohydramnios, hypertensive disorder of pregnancy, gestational diabetes, & maternal drug abuse.  MSAF at delivery is a potential sign of foetal compromise. The presence of meconium is an indication for continuous monitoring of the foetal heart rate (FHR) during labour and it lowers the threshold for making a diagnosis of foetal distress if FHR abnormalities are present.  Unfortunately, there is no definitive test that confirms the clinical impression of meconium in amniotic fluid or on histopathological specimen. MAS causes significant respiratory distress because meconium is locally irritative, obstructive and a medium for bacterial growth. This study was conducted to find out the incidence of meconium aspiration syndrome, analyse associated maternal and neonatal risk factors and final outcome in babies born through Meconium-stained amniotic fluid in a tertiary health care setting.
* To find out the rate of Meconium aspiration syndrome (MAS) in babies born with Meconium-stained amniotic fluid (MSAF) in GGH, Guntur.
* To analyse the associated maternal and neonatal risk factors associated with Meconium aspiration syndrome (MAS),
* To evaluate the outcome of Meconium aspiration syndrome (MAS).
MATERIALS AND METHODS
The study was a prospective, hospital based, observational study done in a tertiary health care setting in the Department of Paediatrics, Government General Hospital, attached to Guntur Medical College, Guntur, Central Andhra Pradesh, South India. During the study period (October 2015 to February 2016 (5 months), there were 2,380 live births, of which only 160 had (6.7%) MSAF. MAS developed in 21 of these infants (13.12%). Hence, the present study was conducted among 160 Neonates.
Neonates born with Meconium-stained amniotic fluid and/or meconium staining of nails/cord/skin that fulfilled the eligibility criteria of MAS were included in the study group. Those babies whose parents gave consent were included.
Babies born with prematurity and with congenital anomalies and whose parents didn't give consent were excluded from the study.
The study was approved by the institutional Ethics Committee. A written consent was obtained from either of the parents of the baby.
The data was recorded in a pre-designed proforma with all details including laboratory examination findings and was analysed using SPSS 18 version software.
A total of 2,380 live births occurred during the period of October 2015 to March 31st 2016. Only 160 (6.7%) had MSAF. MAS developed in 21 of these infants (13.12%). Out of 160 cases, babies with SGA were 105 (65.62%), AGA were 55 (34.38%) and LGA were nil in our study which is depicted in Table: 1.
It was found that the Incidence of MSAF was 67 per 1000 live births. Among them (160 cases with MSAF), only 21 (13.12%) developed MAS.
Out of 160 cases with MSAF, 92 (57.5%) babies were male and 68 (42.5%) were female. Out of 160 cases with MSAF, term babies were 156 (97.5%), and post-term were 4 (2.5%).
Babies born to mothers with oligohydramnios with MSAF had 2.81 times more risk of developing MAS than nonoligohydramnios cases which is depicted in Table 2.
Babies born to post-term pregnancy with MSAF had 7.21 times more risk of developing MAS than with term pregnancy which is depicted in Table 3.
Babies born with APGAR<7 with MSAF had 16.62 times more risk of developing MAS than with babies of APGAR>7 which is depicted in Table 4.
Babies of SGA with MSAF had 3.58 times more risk of developing MAS than with non-SGA babies which is depicted in Table 5.
Out of 21 cases with MAS, 9 required ventilation, of which 5 (55.5%) cases needed CPAP support and 4 (19.04%) cases needed invasive mechanical ventilation which is depicted in Table 6. Out of 21 cases with MAS, 16 (76.19%) cases were discharged and 5 (23.80%) babies died which is depicted in Table 7.
Odds ratio- 29.701 (95% CI): 2.81(1.01-7.08) *Chi-square value= 102.553 df = 1 p=0.000
Odds ratio (95% CI) : 7.21 (1.75-4.64) i.e. Babies born to post-term pregnancy with MSAF had 7.21 times more risk of developing MAS than with term pregnancy.
Odds ratio (95% CI): 16.62(5.06-54.65) i.e. babies born with APGAR<7 with MSAF had 16.62 times more risk of developing MAS than with babies of APGAR>7. *Statistically significant p<0.05
Odds ratio (95% CI) : 3.58(1.01-12.76) i.e. Babies of SGA with MSAF had 3.58 times more risk of developing MAS than with non -SGA babies. *Statistically significant p<0.05
Out of 21 cases with MAS, 16 (76.19%) cases were discharged and 5 (23.80%) babies died.
Meconium aspiration syndrome (MAS) is a common neonatal problem associated with Meconium-stained amniotic fluid (MSAF). Aspiration can occur with foetal gasping or after birth with first breaths of life. Meconium aspiration can lead to increased perinatal morbidity and mortality and the majority of infants born with MSAF show no long-term impairments.
In our study, the incidence of MSAF is 6.7% which is comparable to other studies made by Patii et al,  (8.3%), Fischer et al (7.93%>). The incidence of MSAF greatly varies in different reports from 7-22%.
In the present study, the incidence of post-term babies with MSAF is 4 (2.5%) which is low compared to other studies like Naveen et al which is a community based prospective study.
The incidence of meconium aspiration syndrome (MAS) in babies born to mothers with Meconium-stained amniotic fluid (MSAF) in our study was 21 (13.12%) which is comparable with other studies like Cleary GM et al C13) 1896 (15.59%) and Patii et almi 32 (12.9%).
In our study, the number of babies with MAS in post-term pregnancy (50%) is high compared to other studies like Mohammad Reza Sedaghatian et al 2 (6.6%) which is a community based study. This may be because of less number of post-term deliveries in our study.
In our study, the number of babies with MAS with APGAR <7 is 60% which is comparable with other Indian studies like Patii et al  (66.6%).
Regarding Neonatal Mortality outcome of Babies with MAS & MSAF in our Study
Out of 21 cases with MAS, 16 (76.19%) cases were discharged and 5 (23.80%) babies died. From the literature, [15, 16] the mortality of babies with MAS ranged from 0 to 30%. The higher mortality in our study may be attributed to the high number of high risk pregnant mothers referred to our tertiary care centre.
Meconium-stained amniotic fluid (MSAF) affects mostly full term and post-term babies. MSAF alone is not associated with an adverse neonatal outcome, majority of the babies remain asymptomatic in spite of MSAF and require only routine care. Increased incidence of MAS was found in babies who had Post-term pregnancy, SGA babies, oligohydramnios, Apgar score <7 and associated medical illness in the mother. These babies required ventilator support, hence they require continuous and close monitoring. Hence, the management is a combined approach of an Obstetrician and a Paediatrician, right from proper monitoring of maternal risk factors to meticulous newborn resuscitation and post-resuscitation care in a tertiary level neonatal intensive care unit.
 Fanaroff AA. Meconium aspiration syndrome: historical aspects. Journal of Perinatology 2008;28 Suppl 3:S3-7.
 Kelly P. First-year baby care. Simon and Schuster 2011.
 Guha DK. Neonatal asphyxia, resuscitation and beyond. Jaypee 2008.
 Anwar Z, Butt TK, Kazi MY. Mortality in meconium aspiration syndrome in hospitalized babies. J Coll Physicians Surg Pak 2011;21(11):695-9.
 Garg N, Choudhary M, Sharma D, et al. The role of early inhaled budesonide therapy in meconium aspiration in term newborns: a randomized control study. The Journal of Maternal-Fetal & Neonatal Medicine 2016;29(1):36-40.
 Yelamanchili A, Dasari US, Cherukuri K. Role of transcervical amnioinfusion in labour complicated with thick meconium stained liquor. Journal of evidence based medicine and healthcare 2015;2(42):7202-7.
 Bhutta ZA, Das JK, Bahl R, et al. Can available interventions end preventable deaths in mothers, newborn babies, and stillbirths, and at what cost? The Lancet 2014;384(9940):347-70.
 Espinheira MC, Grilo M, Rocha G, et al. Meconium aspiration syndrome-the experience of a tertiary center. Revista Portuguesa de Pneumologia 2011;17(2):71-6.
 Monen L, Hasaart TH, Kuppens SM. The aetiology of meconium-stained amniotic fluid: pathologic hypoxia or physiologic foetal ripening? (Review). Early human development 2014;90(7):325-8.
 Kumar P, Halamek LP. Resuscitation of the fetus and newborn, an issue of clinics in perinatology. Elsevier Health Sciences 2012;39(4):15-6.
 Kamal PP, Swamy MK, Samatha K. A one year cross sectional study of management practices of meconium stained amniotic fluid and perinatal outcome. The Journal of Obstetrics and Gynecology of India 2006;56(2):128-30.
 Fischer C, Rybakowski C, Ferdynus C, et al. A population-based study of meconium aspiration syndrome in neonates born between 37 and 43 weeks of gestation. International Journal of Pediatrics 2012;2012:1-7.
 Cleary GM, Wiswell TE. Meconium-stained amniotic fluid and the meconium aspiration syndrome an update. Pediatr Clin N Am 1998;45(3):511-29.
 Sedaghatian MR, Othman L, Rashid N, et al. Abdul bari bener 8-year study of meconium stained amniotic fluid in different ethnic groups. Kuwait Medical Journal 2004;36:266-9.
 Naveen S, Sharma VK, Sarin R, et al. Predictors of meconium stained amniotic fluid: a possible strategy to reduce neonatal morbidity and mortality. J Obstet Gynecol India 2006;56(6):514-7.
 Louis D, Sundaram V, Mukhopadhyay K, et al. Predictors of mortality in neonates with meconium aspiration syndrome. Indian Pediatr 2014;51(8):63740.
Thirupathi Reddy Avula (1), Suneetha Bollipo (2), Suneetha Potharlanka (3)
(1) Associate Professor, Department of Paediatrics, Guntur Medical College, Guntur.
(2) Assistant Professor, Department of Paediatrics, ACSR Government Medical College, Nellore.
(3) Junior Resident, Department of Paediatrics, Guntur Medical College, Guntur.
Financial or Other, Competing Interest: None. Submission 18-07-2017, Peer Review 19-08-2017, Acceptance 26-08-2017, Published 31 -08-2017.
Dr. Suneetha Bollipo, Flat No. 502, Magnolia Apartment, Opposite LG Showroom, Ring Road, Guntur-522007, Andhra Pradesh.
Table 1. Distribution of MSAF Cases According to Gestational Age and Birth Weight Classification of Baby No. of Cases n (%) SGA (Small for gestational age) 105 (65.62%) AGA (Appropriate for gestational age) 55 (34.38%) LGA (Large for gestational age) 0 Table. 2 Distribution of Babies with MSAF and MAS According to Oligohydramnios Oligohydramnios* Meconium Aspiration Syndrome (MAS) Total n (%) YES n (%) NO n (%) Yes 7 (4.38%) 21(13.12%) 28 (17.5%) No 14 (8.75%) 118 (73.75%) 132 (82.5%) Total 21 (13.13%) 139 (86.87%) 160 (100%) Odds ratio- 29.701 (95% CI): 2.81(1.01-7.08) * Chi-square value= 102.553 df= 1 p=0.000 Table. 3 Distribution of MSAF and MAS According to Post-Term Pregnancy Post-term Pregnancy* Meconium Aspiration Total n (%) Syndrome (MAS) YES n (%) NO n (%) Yes 2 (1.25%)* 2 (1.25%) 4 (2.5%) No 19 (11.88%) 137 (85.62%) 156 (97.5%) Total 21 (13.13%) 139 (86.87%) 160 (100%) Odds ratio (95% CI) : 7.21 (1.75-4.64) i.e. Babies born to post-term pregnancy with MSAF had 7.21 times more risk of developing MAS than with term pregnancy. Table 4. Distribution of MSAF Cases with and without MAS According to Apgar <7 APGAR <7 * Meconium aspiration syndrome (MAS) Total n (%) YES n (%) NO n (%) Yes 9 (5.62%) 6 (3.76%) 15 (9.38%) No 12 (7.5%) 133 (83.12%) 145 (9062%) Total 21 (13.12%) 139 (86.88%) 160 (100%) Table 5. Distribution of MSAF and MAS According to Small for Gestational Age (SGA) Small for Gestational Meconium Aspiration Total n (%) Syndrome (MAS) YES n (%) NO n (%) Age (SGA) * Yes 18(11.25) 87 (54.38%) 109 (65.63%) No 3 (1.87%) 52 (32.5%) 55 (34.37%) Total 21 (13.12%) 139 (86.88%) 160 (100%) Odds ratio (95% CI) : 3.58(1.01-12.76) i.e. Babies of SGA with MSAF had 3.58 times more risk of developing MAS than with non-SGA babies. * Statistically significant p<0.05 Table 6. Distribution of MAS Cases According to the need for Ventilatory Support Type of Ventilation No. of Cases n (%) CPAP 5 (55.5%) Mechanical ventilation 4 (44.5%) Total 9 (100%) Table 7. Distribution of MAS cases According to Immediate Neonatal Outcome Outcome No. of Cases n (%) Discharged 16 (76.19%) Death 5 (23.80%) Out of 21 cases with MAS, 16 (76.19%) cases were discharged and 5 (23.80%)) babies died.
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|Title Annotation:||Original Research Article|
|Author:||Avula, Thirupathi Reddy; Bollipo, Suneetha; Potharlanka, Suneetha|
|Publication:||Journal of Evolution of Medical and Dental Sciences|
|Date:||Aug 31, 2017|
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