Uterine artery Doppler velocimetry in patients with idiopathic hydramnios.

OBJECTIVE: To evaluate the role of overdistended uterus on the uterine artery (UA) blood flow velocimetry by comparing UA Doppler in patients with idiopathic hydramnios to patients with normal amniotic fluid (AF) volume. METHODS: Pulsatility index (PI) of both UAs was determined prospectively between 26 and 41 weeks of gestation in 72 consecutive pregnant women with singleton pregnancies and idiopathic hydramnios and in 72 pregnant women with normal AF volume. Hydramnios was defined as an AF index (AFI) above 24 cm. A normal amount of AF was defined as an AFI of 6-24 cm. Patients with known fetal structural or chromosomal anomalies and those with diabetes mellitus were excluded. RESULTS: No significant differences were observed between the groups with regard to maternal age, gravidity, and gestational age at examination. Gestational age at delivery and accordingly birth weight were significantly lower in patients with hydramnios compared to those with a normal AFI (34.9 +/- 2.1 vs. 39.1 +/- 1.2, p < 0.001; 2,508 +/- 399 vs. 2,995 +/- 420, p < 0.001, respectively). No significant differences were noted between right UA PI (0.73 +/- 0.3 in the hydramnios group vs. 0.71 +/- 0.2 in the control group; p = 0.091) and left UA PI (0.91 +/- 0.3 in the hydramnios group vs. 0.84 +/- 0.3 in the control group; p = 0.131) of both groups. CONCLUSION: UA velocimetry in patients with idiopathic hydramnios was not significantly different from those with a normal AF volume.