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What is pre-eclampsia?

Pre-eclampsia is a condition that affects some pregnant women.

Pre-eclampsia usually happens during the second half of pregnancy by the new onset of high blood pressure and protein in the urine. Most cases are mild and without symptoms. But sometimes the mother becomes seriously unwell and her baby is very small and may need neonatal care.

It is a condition that impacts up to 8 in 100 pregnant women.

What are the symptoms of pre-eclampsia?

Most women with pre-eclampsia have no symptoms.

Most women with the following symptoms do not have pre-eclampsia, but severe cases can be associated with the following:

  • Headache
  • Blurred vision or flashing lights
  • Pain below the ribs
  • Vomiting
  • Heartburn
  • Swelling of the face, hands or feet

If you develop these symptoms, call your midwife, GP surgery or NHS 111.

Pre-eclampsia is identified by the following signs:

  • New onset high blood pressure
  • Protein in the urine

These should be picked up in routine antenatal appointments.

Most cases of pre-eclampsia are mild, but left untreated, pre-eclampsia can lead to serious complications. The earlier it is diagnosed and monitored, the better for a woman and her baby.

Are there certain risk factors that can increase my chance of pre-eclampsia?

The exact cause of pre-eclampsia is unknown, but it’s thought to occur when there’s a problem with the placenta in a woman with a tendency to high blood pressure.

Several factors that can increase your risk of pre-eclampsia include:

  • 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, such as lupus

Other factors that can increase your risk include:

  • First pregnancy
  • Family history of pre-eclampsia
  • More than 10 years since a previous pregnancy
  • Having a body mass index (BMI) of 35 of more
  • Expecting more than one baby
  • Being 40 years old or more

If you’re thought to be high risk, you may be advised to take aspirin 150mg daily each evening from the 12th week of pregnancy until the 36th week.

How is pre-eclampsia diagnosed?

It is usually diagnosed during antenatal appointments when the blood pressure is high and a urine sample contains excessive protein.

If you are between 20 and 35 weeks pregnant, and you have high blood pressure, your doctor will arrange blood tests. One of these blood tests is aimed to rule out the possibility that your placenta is causing pre-eclampsia. Other blood tests determine the severity of pre-eclampsia.

Can pre-eclampsia be treated?

If you are diagnosed with pre-eclampsia, you will be referred for an assessment to determine whether a hospital stay is required. Your blood pressure will be measured regularly, and you may be given blood pressure lowering medication. You will also have urine tests and blood tests. Your baby’s heart rate will be monitored, and their growth and wellbeing will be checked with ultrasound scans.

The only cure for pre-eclampsia is delivering the baby, so you’ll be regularly monitored until this is possible. Timing of delivery will depend on the severity of pre-eclampsia for mother and baby, and how many weeks into the pregnancy you are.

What are the possible complications of pre-eclampsia?

If left untreated, pre-eclampsia may lead to a number of serious complications. These include convulsions (eclampsia), stroke and ‘placental abruption’, when the placenta comes away from the inner lining of the womb.

A severe complication of pre-eclampsia is the HELLP syndrome, a combined liver and blood clotting disorder. This complication is rare.

Will I get pre-eclampsia in a future pregnancy?

One in six women who have had pre-eclampsia will get it again in a future pregnancy. Recurrent pre-eclampsia is more common if it occurred early and severely in the first pregnancy.

Every woman’s experience is different. You should be given information about your specific chance of pre-eclampsia in a future pregnancy by your doctor or midwife. Contact your midwife as soon as possible once you know you are pregnant again.

For more information and support, please visit:

NHS website

Tommy's

Action on Pre-eclampsia

Royal College of Obstetricians and Gynaecologists

NICE Guidelines: Hypertension in pregnancy: diagnosis and management