DOPPLER ULTRASONOGRAPHY IN HIGH-RISK PREGNANCIES - SYSTEMATIC REVIEW WITH METAANALYSIS

OBJECTIVE: Our objective was to review all available (published and un published) randomized controlled trials of Doppler ultrasonography of the umbilical artery in high-risk pregnancies. STUDY DESIGN: Only comp leted randomized controlled trials were included and reviewed accordin g to the prespecified protocol. Data were sought for 24 prespecified p erinatal outcomes. All meta-analyses were based on the ''intention to treat.'' Primary outcome was defined as perinatal death (any death in utero or postnatally recorded during duration of individual randomized controlled trial). Reported perinatal outcomes that were not prespeci fied were meta-analyzed on a post hoc basis. RESULTS: Twenty randomize d controlled trials of Doppler ultrasonography were identified; 12 ful filled the prespecified criteria. Meta-analysis shows a significant re duction in the number of antenatal admissions (44%, 95% confidence int erval 28% to 57%), inductions of labor (20%, 95% confidence interval 1 0% to 28%), and cesarean sections for fetal distress (52%, 95% confide nce interval 24% to 69%) in the Doppler group and that the clinical ac tion guided by Doppler ultrasonography reduces the odds of perinatal d eath by 38% (95% confidence interval 15% to 55%). The reduction in per inatal deaths was also observed in five mortality subgroups (i.e., sti llbirths, neonatal deaths, deaths of normally formed babies, normally formed stillbirths, and deaths of normally formed neonates). Post hoc analyses revealed a statistically significant reduction in elective de livery, intrapartum fetal distress, and hypoxic encephalopathy in the Doppler group. CONCLUSION: There is now compelling evidence that women with high-risk pregnancies, including preeclampsia and suspected intr auterine growth retardation, should have access to Doppler ultrasonogr aphic study of umbilical artery waveforms.