It usually arises during the second half of pregnancy, but can occur some days after delivery.

In the mother, it can cause several problems, of which she may be unaware, such as high blood pressure, leakage of protein into the urine, thinning of the blood, and liver dysfunction.

In severe pre-eclampsia, symptoms can appear, including severe headaches, visual disturbances (such as flashing lights), vomiting and pain in the upper abdomen. Occasionally, pre-eclampsia can lead to convulsions, a serious complication known as eclampsia.

When a pregnancy is complicated by PE, the baby may grow more slowly than normal in the womb or suffer a potentially harmful oxygen deficiency.

Source: AAPE, courtesy of the Royal Women's Hospital, Melbourne