Meconium Stained Amniotic Fluid and Perinatal Outcome – A Prospective Cross Sectional Study

Abstract

Background and objectives The significance of meconium in amniotic fluid is a widely debated subject. Traditionally meconium has been viewed as a harbinger of impending or ongoing fetal compromise; however some of the investigators believe that it is not associated with fetal hypoxia, acidosis or fetal distress, but a physiological process due to gut maturity. In this study we attempt to find out the incidence of meconium staining and its effect on fetal parameters like heart rate, morbidity and mortality and whether the mode of delivery has an effect on the perinatal outcome and if a caesarean section is necessary in such cases. Methods: This prospective cross-sectional study was conducted in Department of Obstetrics and Gynecology at KLE University’s Dr. Prabhakar Kore Charitable Hospital and MRC between January 2013 to October 2013. A total of 340 pregnant women with more than 37 weeks of gestation were included in the study. Effect of thin and thick meconium on fetus was studied. Fetal monitoring, mode of delivery, age distribution, parity, indication for LSCS, cardiotocography, Apgar score, birth weight, resuscitation of baby were the parameters studied. All babies were followed up to discharge from the hospital. Result: In this study the incidence of meconium stained amniotic fluid was 8.5%. Among 340 cases the incidence of thick meconium stained was 57.65%, whereas 42.35% of cases were thin meconium stained liquor. Maximum incidence of meconium stained amniotic fluid was seen in age group 22-25 i.e.157 (46.1%). Meconium stained amniotic fluid was more common in 37-40 weeks of gestation. Post datism contributed to 25.5% of the risk factors. CTG was pathological in 73.60% especially in thick meconium, compared to thin meconium which was 26.4% Incidence of operative interventions were increased in thick meconium stained (79.5%) compared to thin meconium stained deliveries (20.5%). Lower segment caesarean section was more seen in early labour in cases with thick meconium stained amniotic fluid. One of the most common indication for LSCS was fetal distress in thick meconium stained liquor (72.96%). The incidence of Apgar score >7, at 1 minute, for thin and thick meconium was 52.2% and 47.8% respectively. The incidence of Apgar score <7, for thin and thick was 68.4% and 31.6% respectively. Apgar score at 5 minute is mostly >7 in thin meconium i.e., 139 (43.71%) and 179 in thick meconium (56.29%). Apgar score <7 in thin and thick meconium was 5 and 17. Out of 340 cases, 76 babies needed NICU admissions. Birth asphyxia attributed to 6.63% of NICU admission in thick meconium stained liquor and 2.7% in thin meconium stained liquor 3 cases of perinatal mortality was seen in in thick meconium stained. Neonatal deaths were seen in 0.88%. Interpretation and Conclusion: Thus based on our findings we conclude that the rates of caesarean section were higher in patients with thick meconium stained liquor. Cardiotocography abnormalities, Lower apgar scores at 1 and 5 minutes were observed more in thick meconium stained liquor than in thin meconium stained liquor. However the perinatal outcomes in the thick and thin meconium stained liquor groups were insignificant.