Discordant uterine artery velocity waveforms as a predictor of subsequent miscarriage in early viable pregnancies

OBJECTIVE: Our purpose was to determine whether an abnormal uterine perfusi on pattern was associated with subsequent pregnancy loss after fetal cardia c activity was documented. STUDY DESIGN: Pulsatility indexes of both the right and left uterine arteri es were obtained by transvaginal color Doppler ultrasonography in 318 conse cutive viable pregnancies between 6 and 12 weeks' gestation. The Delta uter ine artery pulsatility index value, expressed as the highest uterine artery pulsatility index Value minus the lowest value, was calculated for each pr egnancy. Women were subsequently classified as having continuing pregnancie s or pregnancy loss before 20 weeks' gestation. To predict subsequent pregn ancy loss, Doppler findings were adjusted for maternal age, history of prev ious abortion, presence of subchorionic hematoma, embryonic bradycardia, an d gestational age by means of multivariate logistic regression analysis. RESULTS: Twenty-four pregnancies (8%) were spontaneously aborted before 20 weeks' gestation. Both Delta uterine artery pulsatility index (odds ratio 2 .9, 95% confidence interval 1.5-5.8) and history of previous abortion (odds ratio 3.1, 95% confidence interval 1.2-8.2) were significantly associated with pregnancy loss in the multivariate logistic regression analysis. The s ensitivity and specificity of the multivariate logistic regression model to predict abortion were 75% and 85%, respectively, significantly higher than the diagnostic performances of qualitative and quantitative variables cons idered individually. CONCLUSION: Discordant uterine artery pulsatility indexes in the first trim ester were strongly associated with subsequent pregnancy loss. This suggest s that uterine ischemia may be implicated in certain cases of early pregnan cy loss after documentation of fetal cardiac activity during the first trim ester.