Aminotic Fluid Index and its Correlation with Fetal Growth and Perinatal Outcome

Abstract The present study aimed to measure amniotic fluid index (AFI) in high-risk pregnancies at ≥30 weeks of gestation and its correlation with fetal growth and perinatal outcome. The Study was carried out in the Department of Obstetrics and Gynecology Hindu Rao Hospital, Delhi. Ultrasound examination was done on women with high-risk pregnancy (pregnancy-induced hypertension, intrauterine growth restriction, diabetes, and postdated pregnancy etc.) attending the antenatal OPD and maternity ward at ≥30 weeks of gestation. AFI was measured by the four quadrant technique. The study included 48 (48 %) primigravida and 52 (52 %) multigravida. Sixteen patients with a history of previous abortion had mean AFI of 9.97 cm which was lower than patients with no history of previous abortion i.e., 11.87 cm (P ≥ 0.1 insignificant). The mean AFI was maximum between 34–36 weeks, i.e., 13.1 cm, after which, it gradually decreased to 9.08 cm beyond 40 weeks. Mean AFI of patients with <40 weeks of gestation gradually decreased from 12.2 cm to 8.0 cm after 42 weeks (P value <0.05). Patients with IUGR had low mean AFI i.e., 9.8 cm whereas mean AFI in patients without IUGR was 12.1 cm (P value <0.01). Congenital anomalies were found in 4 % patients in the present study. Out of seven cases of perinatal mortality encountered, four (57 %) had abnormal AFI values, of which, two had low AFI (i.e., <8 cm) and two had abnormally-high AFI values i.e., >18 cm. Serious congenital malformations were present in three neonates, which resulted in early neonatal death. Out of these three, one patient had low AFI i.e., <8 cm and one had abnormally-high AFI value i.e., >24 cm. The study supports the view that AFI is a quick, noninvasive, and good indicator of fetal outcome in high-risk pregnancy.