The use of umbilical artery Doppler velocimetry in the monitoring of pregestational diabetic pregnancy

Abstract

Purpose: To assess whether umbilical artery Doppler velocity waveform analysis can predict adverse perinatal outcomes for pregnancies complicated with pre‐existing diabetes mellitus (types 1 and 2 diabetes mellitus).Methods: All diabetic pregnancies (types 1 and 2) delivered at Mater Mothers' Hospital, Australia, between 1st January 1995 and 31st December 1999, were included. All pregnant diabetic women were monitored with umbilical artery Doppler velocimetry at 28, 32, 36, and 38 weeks gestation. Umbilical artery Doppler study was repeated on weekly basis for pregnancies complicated by macrosomia, polyhydramnios, or fetal growth restriction. Adverse perinatal outcome was defined as pregnancies with one or more of the following: small‐for‐gestational age (birth weight <10th centile), cesarean section for non‐reassuring cardiotocography, fetal acidemia at delivery (cord blood arterial pH < 7.2), 1‐min Apgar of ≤3, 5‐min Apgar of <7, hypoxic ischaemic encephalopathy, stillbirth and perinatal deaths. Abnormal umbilical artery Doppler index was defined as systolic/diastolic ratio of 95th centile or higher for gestation (including absent or reversed end‐diastolic flow). The incidence of adverse perinatal outcomes was compared between those with normal umbilical artery Doppler and those with elevated systolic/diastolic (S/D) ratio.Results: One hundred and four pregnancies had umbilical arterial Doppler studies performed during the study period. Twenty‐three pregnancies (22.1%) had elevated S/D ratio of the umbilical artery Doppler velocimetry. If the scans were performed within 2 weeks of delivery, 71% of pregnancy with abnormal umbilical Doppler study have adverse outcome. For umbilical artery Doppler studies performed within 1 week of delivery, the sensitivity was 35%; specificity was 94%; positive predictive value was 80%; and negative predictive value was 68%. However, only 30% of women with adverse perinatal outcomes had abnormal umbilical Doppler flow.Conclusion: Elevated umbilical arterial Doppler S/D ratio is associated with adverse perinatal outcomes. However, the majority of diabetic pregnancies with adverse perinatal outcomes have normal umbilical artery Doppler velocimetry. Thus, this could be a useful test for monitoring, but is not a good predictor of adverse perinatal outcomes.