Risks of high blood pressure in pregnancy - High blood pressure in pregnancy and pre-eclampsia

High blood pressure during pregnancy can cause complications for you and your baby.

Restrict your baby's growth

High blood pressure can reduce blood flow through the placenta (afterbirth). This can restrict your baby's growth.

When you have high blood pressure in pregnancy, you will need to have more frequent scans. This is to ensure that the baby is healthy and growing well.

The scan will usually involve a Doppler scan that checks the blood flow in the baby’s umbilical cord. This helps to tell how well the placenta (after-birth) is working.

Placental abruption

This is a rare condition where the afterbirth becomes separated from the inner wall of your womb.

Placental abruption causes you to have severe tummy pain and vaginal bleeding. This is dangerous for you and your baby.


Always see your obstetrician or GP urgently if you have severe tummy pain or bleeding from your vagina

Premature or preterm labour

High blood pressure can cause premature or pre-term labour.


Premature labour

Other complications caused by pre-eclampsia

Pre-eclampsia can cause any of the problems that high blood pressure can cause.

Pre-eclampsia can also cause other complications, especially if it is not treated.

Fits (eclampsia)

Eclampsia is a type of fit or convulsion that a pregnant woman can have.

During the fit the woman will have jerking movements of her arms and legs. She may bite her tongue and wet herself. If these fits last a long time they can cause brain damage.

The baby may not receive enough oxygen during a convulsion and may even die.

Blood cell damage and organ damage

Pre-eclampsia can cause red blood cells in your blood to break down. It can also cause the levels of a type of blood cell known as a platelet to fall, and can cause your liver enzymes to rise. This is called HELLP syndrome and is rare.

Organ damage

Pre-eclampsia can damage your lungs, your kidneys and your liver.

Risk of stroke

Pre-eclampsia can increase your risk of having a stroke.

Early delivery

If your pre-eclampsia is severe, your baby may need to be delivered early. This may mean that you need to be induced or to have a caesarean birth.

It may also mean that your baby needs to be delivered before they are fully developed. This can cause breathing problems for a newborn baby.

If your baby needs to be born early, they may need extra care. They might be admitted to the SCBU (special care baby unit) or NICU (neonatal intensive care unit).


Having pre-eclampsia increases your risk of having a stillbirth.

Page last reviewed: 17 September 2018
Next review due: 17 September 2021