Evaluation of cerebroplacental ratio as a new tool to predict adverse perinatal outcomes in patients with isolated oligohydramnios

Abstract

Aim: There is conflicting information in the literature regarding perinatal outcomes and management of isolated oligohydramniotic (IO) pregnancies. Recent studies show that IO is associated with poor perinatal outcomes. However, there is still no definitive method for deciding the optimal delivery timing for these patients. In this study, we aimed to assess the relationship between Doppler parameters, especially cerebro-placental ratio, and perinatal outcomes in isolated oligohydramnios (IO) patients. Methods: This prospective case control study was conducted between October-November 2018. A total of 98 patients were recruited and divided into two groups, as pregnant women with normal amounts of amniotic volume and the isolated oligohydramnios group. Oligohydramnios diagnosis was made by amniotic fluid index measurement (AFI<5 cm). Pregnancies with hypertension, fetal growth restriction, thrombophilia, preeclampsia, diabetes mellitus, preterm births and chromosomal/structural abnormalities were excluded. Cerebro placental ratios of groups were compared in terms of composite adverse outcomes, low APGAR score in 1st and 5th minutes, C/S operation due to non-reassuring fetal heart rate patterns, admission to neonatal intensive care unit and still births. Results: In the isolated oligohydramnios group (n=45) cerebro-placental ratio (CPR) was lower compared to control group (P<0.001). IO was associated with lower (APGAR score<7) 1st (55.6% vs. 7.5%, P<0.001) and 5th (13.3% vs. 1.9% P=0.028) minute APGAR scores and higher rates of NICU admission (26.7% vs. 3.8% P=0.001). Number of fetal distress cases was higher in patients with low CPR in the IO group (9 vs. 6 P=0.023). Conclusion: Measurement of CPR among IO patients seems useful for detection of fetuses with higher risk for poor neonatal outcomes.