A lower reduction in umbilical artery pulsatility in mid-pregnancy predicts higher infant blood pressure six months after birth

AIM: The Norwegian-based Cardiovascular Risk Reduction Diet in Pregnancy study found that a cholesterol-lowering diet during pregnancy was associated with an accentuated reduction in the umbilical artery pulsatility index. This follow-up study assessed the possible association between the index and the infants' blood pressure at six months of age.

METHODS: In the original study, pregnant women consumed an anti-atherogenic or usual diet from gestational weeks 17-20 to birth and underwent Doppler velocimetry at 24, 30 and 36 gestational weeks. In this follow-up study, blood pressure was measured in 105 mother-infant pairs in the intervention group and 106 mother-infant pairs in the control group six months after birth.

RESULTS: Mean systolic and diastolic blood pressures were not significantly different between both groups. When the groups were combined, multivariate linear analyses showed that a lower versus higher reduction (≥-0.17 versus <-0.17) in the umbilical artery pulsatility index between gestational weeks 24 and 30 and maternal diastolic blood pressure at six months postpartum were significant predictors of higher infant systolic blood pressure (p = 0.03, 0.01, respectively).

CONCLUSION: A lower reduction in umbilical pulsatility index in mid-pregnancy was associated with higher infant blood pressure at six months of age. This suggests that fetoplacental intrauterine factors may influence future cardiovascular risk.