What is pre-eclampsia?

Pre-eclampsia is condition that can affect pregnant women. You can only get it when you’re pregnant.

Pre-eclampsia causes high blood pressure for the mother. This means your baby will not get as much essential blood. Your organs will get less blood too.

Thankfully, most cases of pre-eclampsia are mild without symptoms. But it can make some mothers and their babies very unwell if it’s not treated. You will have extra, specialist care if you have signs of pre-eclampsia.

How common is pre-eclampsia?

Pre-eclampsia is more common in first pregnancies. Around 1 in 25 first-time mums have it. And around 1 in 60 have it in second pregnancies.

Because pre-eclampsia is quite common, women are tested for it throughout their pregnancies. This means it can be caught and treated before it gets serious.

It’s rare for pre-eclampsia to happen before you’re 20 weeks pregnant. Most cases happen near the end of pregnancy.

What causes pre-eclampsia?

Pre-eclampsia is thought to happen when the placenta does not work properly. This then causes high blood pressure for the mother.

High blood pressure in turn means there is less blood going back to the placenta.

Your baby needs this blood for their oxygen, nutrients and antibodies. You will also not get as much blood to your essential organs. These include your liver, kidneys and brain.

Who is at risk?

Several factors can increase your risk of pre-eclampsia:

• high blood pressure, kidney disease or diabetes before pregnancy
• high blood pressure or pre-eclampsia in a previous pregnancy
• having an active autoimmune condition that affects blood vessels. This might be systemic lupus erythematosus (SLE).

Your risk can also increase if:

• it’s your first pregnancy or it’s more than 10 years since your last pregnancy
• you have a family history of pre-eclampsia
• you have a body mass index (BMI) of 35 of more
• you’re expecting more than one baby
• you’re 40 years old or more

If your midwife or doctor thinks you have a high risk of pre-eclampsia, they may prescribe a daily dose of aspirin. You would be prescribed this from the 12th week of pregnancy until your baby is born. Aspirin cuts your risk of pre-eclampsia by more than half.

What are the signs of pre-eclampsia?

In most cases you will not have any obvious symptoms. This is why you’ll have your blood pressure and pee checked regularly during your pregnancy. High blood pressure and protein in your pee can be signs of pre-eclampsia.

These regular tests mean pre-eclampsia can be treated and monitored early. This will help keep you and your baby healthy.

If you do have pre-eclampsia symptoms they might include:

• severe headache
• vision problems, such as blurring or flashing
• pain just below the right rib
• vomiting
• sudden swelling of the face, hands or feet

If you have any of these symptoms, call your GP surgery or NHS 111 straightaway. Left untreated, pre-eclampsia can make you and your baby seriously illl.

How is pre-eclampsia diagnosed?

Pre-eclampsia is usually diagnosed through your regular blood pressure and urine tests. These are carried out during antenatal appointments.

If your blood pressure is high or a urine sample contains too much protein, it could be pre-eclampsia. if you’re between 20 and 37 weeks pregnant your midwife or doctor will send you on for blood tests.

Tests will confirm whether you have pre-eclampsia. They will also check whether pre-eclampsia is damaging your liver or kidneys.

How is pre-eclampsia treated?

If you’re diagnosed with pre-eclampsia, you’ll be referred to hospital for more tests by a specialist.

These tests will check how severe your pre-eclampsia is and whether you need to stay in hospital.

You will probably need medication to lower your blood pressure. Pregnant women  have used labetalol, nifedipine and methyldopa to safely lower blood pressure.

Your blood pressure will be checked regularly during the rest of your pregnancy. You’ll also have regular urine tests and blood tests. Your baby’s heart rate will be monitored, and their growth and wellbeing will be checked.

The only way to stop pre-eclampsia is by having your baby. This means you may need to be induced or have a caesarean so your baby can be born early.

In most cases you’ll be advised to have your baby at around 37 to 38 weeks. But it depends on how serious your pre-eclampsia is. You might be advised to have your baby earlier if it’s making one or both of you ill.

How does pre-eclampsia affect my baby?

Babies of some women with pre-eclampsia grow more slowly than normal. This is because the placenta may not be working as well as it should. Your baby may not then get all the nutrients and oxygen they need.

This is one of the reasons why you will be monitored and why you might need to give birth early.

If your baby is born early they may need help with breathing and feeding. Your baby may need to stay in a neonatal intensive care unit. They can get the extra care they need.

How does pre-eclampsia affect me?

If pre-eclampsia is not diagnosed and treated, it can become serious. Rare but severe complications include:

• fits (seizures) called eclampsia. These affect only 1 in 100 women with pre-eclampsia
• stroke. This is a very rare complication of very high blood pressure
• mini clots in the kidneys, liver and brain. These will stop the organs working properly.
• HELLP syndrome , which is a rare but dangerous type of liver and blood clotting disorder. If you have HELLP syndrome, your baby will need to be born as soon as possible.

You can make a full recovery from these complications as soon as your baby is born.

Living with pre-eclampsia and worrying about the health of you and your baby can be difficult. Speak to your midwife who can offer support.

Will I get pre-eclampsia in a future pregnancy?

1 in 6 women with pre-eclampsia will get it again in a future pregnancy. It’s more common still if you had it early and severely in your first pregnancy.

But every woman’s experience is different. Ask your doctor or midwife for information about your chance of pre-eclampsia in a future pregnancy. Contact your midwife as soon as possible when you are pregnant again.

Getting support

• Charities like Action on Pre-eclampsia and Tommy’s offer more information and support.
• The NHS and the Royal College of Obstetricians and Gynaecologists also have more information.
• NICE produces treatment guidelines and information for women and their families.
• If you need to speak to someone, Action on Pre-eclampsia has a helpline you can call.

Our research on pregnancy and birth

As a women’s health charity, part of what we do is fund research to save and change the lives of women, girls and babies.