Assessment of fetal wellbeing in late pregnancy often does not accurately identify a fetus at risk of adverse outcomes. This results in considerable ‘over treatment’ of women with healthy fetuses whilst the truly compromised fetus remains unidentified. The CPR is the simple ratio of the Umbilical Artery Pulsatility Index over the Middle Cerebral Artery Pulsatility Index. A low CPR is indicative of suboptimal fetal growth and placental insufficiency and a marker of adverse outcomes. Its utility as an indicator for delivery in women with reduced fetal movements is unknown. The primary aim of this study is to assess whether expedited delivery of women with reduced fetal movements identified as high risk on the basis of a low CPR improves neonatal outcomes. Secondary aims include childhood outcomes, detection of maternal hypertensive disorders, and the predictive value of serum biomarkers for adverse outcomes when stratified by CPR.
Design: multicentre cluster randomized clinical trial of women with singleton pregnancies with reduced fetal movements at term randomised to either an unblinded or blinded arm. Only women with an estimated fetal weight >10th centile and normal cardiotocograph are eligible. Expedited delivery is pursued in women with a low CPR in the unblinded arm. Women in the blinded arm will not have their CPR results revealed and will receive routine clinical care.