What causes pre-eclampsia?
It is not known what causes pre-eclampsia. It is thought to occur because of a problem with the placenta, which transfers nutrients and oxygen from the mother to the fetus. There are several factors that may increase the risk of developing pre-eclampsia during pregnancy. Women are more likely to develop pre-eclampsia if they are experiencing their first pregnancy, are overweight, have high blood pressure before they get pregnant, or have a close family member who has experienced pre-eclampsia.