No good evidence that giving the hormone progesterone to pregnant women will help women and babies avoid the problems of pre-eclampsia.
Pre-eclampsia is a serious complication of pregnancy occurring in about 2% to 8% of women. It is identified by increased blood pressure and protein in the urine, but women often suffer no symptoms initially. It can, through constriction of the blood vessels in the placenta, interfere with food and oxygen passing to the baby, thus inhibiting the baby's growth and causing the baby to be born too soon. Women can be affected through problems in their kidneys, liver, brain, and clotting system. One theory is that is that pre-eclampsia might be associated with a shortage of progesterone, and so it has been suggested that giving women progesterone during pregnancy might help them to avoid pre-eclampsia. The review found four trials involving 1445 women. There were insufficient data be to be able to say if progesterone helped, and there was very little information on potential adverse outcomes. So progesterone should not be used in pregnancy for the purpose of trying to reduce the incidence of pre-eclampsia, and further testing is needed.