Clinical use of Doppler ultrasound in pregnancy: information from six randomised trials

The objective of this report was to undertake an overview of the clinical utility of umbilical Doppler ultrasound in the management of high-risk pregnancies. The study is designed as a formal meta-analysis of 6 randomised trial reports selected by predetermined criteria and was performed at the Division of Reproductive Medicine, Newcastle University, Australia. A total of 6 randomised controlled trials amounted to 2,102 patients in the experimental (Doppler) group and 2,133 patients in the control group. All patients had high-risk pregnancies. The management of pregnancies with Doppler was compared to those with standard obstetric management (i.e. excluding Doppler). Main outcome measures were perinatal mortality in the form of intrauterine deaths as well as obstetric performance indicators including caesarean section, elective delivery, fetal distress in labour, antenatal admissions and admissions to Neonatal Intensive Care Unit. The meta-analysis shows a significant reduction in perinatal mortality in the groups in which Doppler was used. Typical odds ratio was 0.5 [95% confidence intervals (CI) 0.34, 0.73]. The specific reduction in perinatal mortality occurred in intrauterine deaths in otherwise normally formed fetuses. The typical odds ratio was 0.54 with 95% CI 0.32, 0.89. This meta-analysis shows a significant reduction in overall perinatal mortality, specifically in the form of intrauterine deaths in otherwise normally formed babies.