IDIOPATHIC POLYHYDRAMNIOS - ASSOCIATION WITH FETAL MACROSOMIA

PURPOSE: To determine the relationship between idiopathic polyhydramni os and fetal macrosomia in the absence of maternal diabetes. MATERIALS RND METHODS: Idiopathic polyhydramnios was studied with ultrasound (U S) in 99 consecutive normal fetuses of nondiabetic women. Birth weight s and estimated fetal weights were compared with those of postnatal an d prenatal control groups, respectively. RESULTS: The mean birth weigh t for the study (polyhydramnios) group was 3,771 g +/- 572 (standard d eviation) compared with 3,476 g +/- 444 for the postnatal control grou p (P <.001). Birth weights in the 90th percentile or greater occurred in 28.2% of the study group versus 9.3% of the postnatal control group (P <.001) with a relative risk of 3.0 and a 95% confidence interval o f 1.9, 4.9. The mean percentile of estimated fetal weight obtained wit h US was also significantly greater for the study group (79.3 +/- 23.7 ) than for the prenatal control group (51.5 +/- 32.7) (P <.001). CONCL USION: Idiopathic polyhydramnios is associated with large-forgestation al-age fetuses and macrosomia independent of maternal diabetes.