IS POLYHYDRAMNIOS ASSOCIATED WITH AN INCREASED UMBILICAL ARTERY SYSTOLIC DIASTOLIC RATIO IN 3RD TRIMESTER GESTATIONS/

Objective: To determine if polyhydramnios is associated with increased systolic/diastolic ratios of umbilical artery Doppler waveforms in th ird trimester fetuses and to assess the clinical significance of pregn ancies complicated by both conditions. Methods: From January 1, 1992 t o July 1, 1994 an amniotic fluid index was measured prospectively in 3 677 third trimester women. Polyhydramnios was defined as an amniotic f luid index of >24 cm. A systolic/diastolic ratio larger than the 95th percentile for gestational age was defined as abnormal. A computer sea rch of all newborn deliveries during the study period was performed to identify infants born with structural or chromosomal anomalies. Chi-s quare and Fisher exact tests were utilized for statistical analysis. R esults: The incidence of chromosomal and structural anomalies among 88 52 deliveries during the study period was 0.14 and 2.3%, respectively. All 65 women with an amniotic fluid index of >24 cm had a systolic/di astolic ratio measured at the same visit. 16/65 (24.6%) had gestationa l diabetes; none of their newborns had a structural or chromosomal abn ormality. An elevated systolic/diastolic ratio was more frequent in pa tients with polyhydramnios when compared with controls (12.3 versus 5% , respectively, P = 0.03). Chromosomal aneuploidies were detected in 2 /8 (25%) patients with polyhydramnios and an elevated systolic/diastol ic ratio compared with 0/57 (0%) patients with polyhydramnios and a no rmal systolic/diastolic ratio (P = 0.02). Structural anomalies were al so more common when polyhydramnios was complicated by an abnormal syst olic/diastolic ratio, Conclusions: 1) Polyhydramnios is associated wit h an increased incidence of an elevated systolic/diastolic ratio. 2) A significantly increased incidence of both chromosomal aneuploidy and structural anomalies occurs in patients with polyhydramnios and an ele vated systolic/diastolic ratio compared with patients having either po lyhydramnios alone or normal amniotic fluid volume.