Pre-eclampsia

Published by Bupa’s Health Information Team, August 2011.

This factsheet is for women who have pre-eclampsia, or for people who would like information about it.

Pre-eclampsia is a condition that can develop in pregnant women. Women with pre-eclampsia have high blood pressure and protein in their urine. Pre-eclampsia can cause eclampsia (fits) and other serious problems. In the baby it can result in growth problems and a premature birth. Severe pre-eclampsia can be life-threatening for both mother and baby.

About pre-eclampsia

Pre-eclampsia is a condition that only develops during pregnancy. It affects both you and your baby and can cause serious health problems if it’s not diagnosed and treated.

Pre-eclampsia starts in your placenta, the organ that links you to your baby. The placenta supplies your baby with the blood and nutrients it needs to grow and develop.

If you have pre-eclampsia, your placenta doesn’t provide enough blood to your baby. This causes your blood pressure to rise and affects how well your kidneys work. As a result of this, protein leaks into your urine. The lack of blood supply to your baby can mean that he or she doesn’t grow properly.

Pre-eclampsia can affect up to one in every 10 pregnancies, though many of these women will have a mild form of the condition. It can develop anytime after 20 weeks of pregnancy until a few days after the birth of your baby.

Pre-eclampsia can develop into a more serious condition called eclampsia. Eclampsia can cause fits and affect major organs in your body such as your liver, kidney and lungs. It can be life-threatening for both you and your baby.

You can also have high blood pressure during pregnancy without having pre-eclampsia. If you have high blood pressure before becoming pregnant, it will usually need to be treated during your pregnancy. You can also develop high blood pressure during pregnancy. This is called pregnancy-induced hypertension and can develop in the second half of your pregnancy, after 20 weeks.

Symptoms of pre-eclampsia

Mild pre-eclampsia doesn’t usually have any symptoms. It’s often picked up at routine antenatal appointments, which is why it’s important to attend these. You will have your blood pressure checked and your urine tested regularly at your antenatal appointments.

Symptoms can develop as pre-eclampsia becomes more severe. These may include:

• headache – usually at the front of your head
• problems with your vision, such as flashing lights and blurred vision
• abdominal (tummy) pain – usually just below your ribs
• feeling or being sick
• feeling confused
• feeling very unwell
• shortness of breath
• sudden swelling of your hands, face or feet

If you are pregnant and have any of these symptoms, you should contact your midwife or GP straight away, or go to the accident and emergency department of a hospital.

Complications of pre-eclampsia

Pre-eclampsia can develop into a condition called eclampsia if it’s not treated. Eclampsia develops in one in every 2,000 pregnant women. It can develop at any time during the second half of pregnancy, during labour or after delivery.

Eclampsia can cause fits, which look similar to epileptic fits. If a fit goes on for a long time, both mother and baby may not receive enough oxygen and this can be life-threatening.

Eclampsia can also lead to liver, kidney and lung failure and problems with blood clotting. A combination of all of these serious health problems is called HELLP syndrome. HELLP syndrome can be life-threatening for the mother and the only treatment is for the baby to be born. This may mean that you have to have your baby early, which can cause other health problems for your baby.

Causes of pre-eclampsia

Doctors don't know the exact cause of pre-eclampsia. However, it seems to start with a problem with the placenta. In pre-eclampsia the placenta doesn’t develop properly, which means there is a reduced blood supply to it.

Doctors don't know why some women get pre-eclampsia and others don't, but there are certain factors that put you at higher risk. Your family history is important. If a close family member, for example your mother or sister, has had pre-eclampsia, you’re more likely to develop it.

You're also more likely to get pre-eclampsia if:

• this is your first baby or your first baby with a new partner
• you had pre-eclampsia in an earlier pregnancy
• you're having twins or other multiple pregnancies
• you're over 40
• you have other medical conditions including high blood pressure, diabetes and kidney disease
• you're very overweight, ie you have a body mass index (BMI) of over 30

Diagnosis of pre-eclampsia

Pre-eclampsia can be difficult to diagnose as there are a large number of different signs and symptoms. Some women have no symptoms at all.

When you go for your regular antenatal appointments you will have your blood pressure checked and your urine tested. If your blood pressure is raised above 140/90mmHg or there is an increase in your diastolic blood pressure reading of more than 20mmHg and the urine test shows that there is protein in your urine, this may show that you have pre-eclampsia.

Your doctor will ask about your symptoms and examine you. He or she may also ask you about your medical history. You may have blood tests to check how well your kidneys are working and how well your blood is clotting.

Treatment of pre-eclampsia

The treatment for pre-eclampsia depends on how severe the condition is, your health and that of your baby, and how many weeks pregnant you are.

If the pre-eclampsia is mild, and you have no symptoms, it may not be necessary for you to be admitted to hospital and you can stay at home. Your midwife and doctor will monitor your blood pressure and test your urine regularly. You will probably also have regular blood tests.

If the pre-eclampsia becomes more severe, you will probably be admitted to hospital where you and your baby can be monitored closely. You will probably have the following tests when you’re in hospital.

• Blood pressure checks about every four hours, or more frequently depending on how serious your condition is.
• Urine collection over 24 hours to measure the exact amount of protein in your urine, followed by daily protein urine checks.
• Blood tests, including kidney, liver and blood clotting tests.
• Ultrasound scans to check the health of your baby.
• Monitoring of your unborn baby’s heart rate to check his or her wellbeing.

Medicines

You may be given medicines to help reduce your blood pressure. These can’t cure pre-eclampsia but they may prevent you developing more serious health problems. Medicines for high blood pressure can be taken as tablets or, if your blood pressure is very high, they may be given through a drip put into a vein in your hand or arm. Your doctor may also give you medicines to prevent fits. These medicines won’t harm your baby.

The only way to ‘cure’ pre-eclampsia is for your baby to be born. Every woman is different, so when this might happen will depend on your health and that of your baby. This may mean that your baby is born early, which may affect his or her health. Your doctor and midwife will discuss this with you.

Prevention of pre-eclampsia

There is nothing specific that you can do yourself that will prevent pre-eclampsia or reduce your risk of developing it. 

If you’re at high risk of developing pre-eclampsia, your doctor may suggest that you take a small amount of aspirin every day. You’re at a high risk of developing pre-eclampsia if you have had the condition in a previous pregnancy, or already have high blood pressure or other health conditions such as diabetes or kidney failure. You will be asked to take aspirin from 12 weeks of pregnancy until your baby is born. You should only take aspirin if your doctor has advised you to.
 

For answers to frequently asked questions on this topic, see Common questions.

For sources and links to further information, see Resources.