Assessment of uterine artery blood flow in normal first-trimester pregnancies and in those complicated by uterine bleeding.

OBJECTIVE: To compare uterine artery blood flow in normal first-trimester pregnancies with those complicated by uterine bleeding. METHODS: Uterine artery blood flow was investigated by transvaginal color Doppler in 46 pregnant women affected by uterine bleeding and in a control group of 35 women with normal intrauterine pregnancy. Gestational age ranged from the 6th to the 12th week. Three blood flow values were calculated, the pulsatility index, the resistance index and the peak systolic velocity. Results were compared between the two groups. RESULTS: Of the 46 patients affected by uterine bleeding, 18 had an incomplete miscarriage, eight had a blighted ovum, five had a missed miscarriage and 15 continued their pregnancy until term and delivered liveborn infants. No significant differences were found in any of the three vascular indices between the normal and the pathological groups of patients. Uterine artery pulsatility and resistance indices decreased with gestational age in both normal and abnormal pregnancies but this change was not statistically significant. The peak systolic velocity significantly increased with gestational age in the control group but not in the pathological group. In patients with a retroplacental hematoma, uterine vascular resistance appeared higher than in those without a hematoma, while the peak systolic velocity showed no difference between the two groups. CONCLUSION: Doppler analysis of the uterine artery blood flow is unlikely to have a clinical role in the management of early pregnancies complicated by uterine bleeding.