Pre-eclampsia is a relatively common condition that can occur during pregnancy and can raise the risk of health complications for mother and baby.

Pre-eclampsia is characterised by high blood pressure (hypertension) which can become very high if not treated.

The condition usually occurs during the second half of pregnancy and treatment involves delivering the baby at the earliest safe stage.

How common is it?

Pre-eclampsia affects up to 5% of pregnancies and tends to be more common in women with diabetes.

Symptoms of pre-eclampsia

Pre-eclampsia causes high blood pressure and also leads to protein in the urine (proteinuria).

If pre-eclampsia develops, it can lead to water retention (oedema) which can lead to one of more of the following symptoms.

If you get these symptoms, it’s important to call your midwife, GP surgery or NHS 111 to arrange diagnosis and treatment.


The cause of pre-eclampsia is not entirely understood but research indicates that the condition stems from problems with blood vessels that supply the placenta

The risk of pre-eclampsia is more likely if this your first pregnancy.

Other risk factors include:

Having diabetes is estimated to double the risk of pre-eclampsia and having kidney disease or high blood pressure can add to the risk.

Research shows that women with diabetes that have protein in their urine as a result of diabetic nephropathy (kidney disease) have around a four times increased risk of developing pre-eclampsia.


Pre-eclampsia will be diagnosed by testing your blood pressure levels and testing for the presence of protein in your urine.

High blood pressure in pregnancy is not always down to pre-eclampsia and can be gestational hypertension in cases where protein is not present in the urine. It is essential to get a diagnosis to confirm and to best treat the condition.

Treating pre-eclampsia

Treatment for pre-eclampsia involves monitoring and managing symptoms such as high blood pressure and aiming for delivery at the earliest safe stage.

Usually delivery will be between 37 and 38 weeks of the pregnancy, which is earlier than the usual full term of pregnancy of around 40 weeks. The delivery may need to be by induced labour or carried out by caesarean section.

If the risk of complications to either mother or baby is high, delivery before 37 weeks may be required.

Prior to delivery, high blood pressure will usually be treated with blood pressure medication.

Complications as a result of pre-eclampsia

Complications as a result of pre-eclampsia can usually be prevented but can occur in some cases.

Complications that can affect the mother include eclampsia, a condition that causes convulsions, and stroke. High blood pressure as a result of pre-eclampsia should usually return to normal blood pressure levels soon after the birth

Pre-eclampsia can lead to a higher risk of organ development problems in babies and stillbirth may occur in some cases.

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