A study on maternal and perinatal outcome of oligohydramnios in term low risk pregnancy

Abstract

Background: Oligohydramnios is a frequent complication of pregnancy that is associated with increased perinatal morbidity and mortality. Once diagnosed; oligohydramnios should further lead to intensive fetal surveillance including ultrasound evaluation. The aim of the study was to determine obstetric outcome in term low risk pregnancy with AFI less than or equal to 5 and to assess whether antepartum oligohydramnios is associated with adverse perinatal outcome.Methods: 200 patients in third trimester in the hospital with evidence of oligohydramnios (AFI less than or equal to 5) were selected after satisfying inclusion and exclusion criteria and studied prospectively. Observations regarding the outcome of labour in form of maternal and perinatal parameters including AFI value, CTG features, mode of delivery, LSCS rate, meconium stained, APGAR score, birth weight and NICU admission were made.Results: Overall perinatal outcome with respect to CTG, 128 (64%) out of 200 patients had non-reactive CTG and only 72 (36%) had reactive CTG. 128 (64%) of non-reactive CTG delivered by LSCS, 72 (36%) delivered by labour natural. Nil labour natural in the subset of AFI 1 to 2, birth weight (<2.5 kg-8% and >2.5 kg-92%), Apgar score (<7 at 1-5 mins:18%), still birth (1%), meconium (58.5%), NICU admission (6%) and perinatal mortality (2%).Conclusions: AFI measurement of less than 5 cm detected after 37 completed weeks of gestation with a low risk pregnancy is found to be an indicator of adverse pregnancy outcome with higher fetal distress, meconium stained liquor and higher caesarean section rate. AFI assessment serves as an important tool and remains as an effective screening test in predicting fetal distress in labour that requires caesarean section.