Identifying the safest blood pressure drugs for use in pregnancy

Evaluation of the safety of maternal anti-hypertensive medicines on placental vascular function

Women with high blood pressure before or during pregnancy need to take blood pressure-lowering medicines throughout pregnancy. These medicines enter the placenta’s circulation – an organ that transfers oxygen and nutrients from the mother’s blood to the foetus. However, it is not known whether these drugs affect its function. There are a range of medicines doctors can prescribe, but there is no clear evidence to help them choose the safest option for pregnant women and their babies. This project will study the effects of various blood-pressure lowering drugs on the placenta’s blood vessels, and how this affects the transfer of oxygen from the placenta to the baby’s developing circulatory system. Dr Paul Brownbill and his team at the University of Manchester will use samples of placentas from women who had a normal pregnancy and those who received blood pressure-lowering medicines during pregnancy. They will keep the placental tissue ‘alive’ under normal blood flow conditions to study the effects of the different treatments. They will use a technique called wire myography to study the chorionic artery, which is responsible for carrying blood to the areas of the placenta with close contact to the foetal circulation. This research should provide the basis of new evidence to help obstetricians prescribe the safest and most effective medications for women with high blood pressure in pregnancy, ensuring the healthy development of their baby.