Pre-eclampsia

Pre-eclampsia is a pregnancy-related condition associated with high blood pressure and sometimes protein in the urine or signs that organs such as the liver or kidneys are affected. It usually develops after 20 weeks of pregnancy, although it can also appear during labour or for the first time after birth.

Many people with pre-eclampsia initially feel well. This is one reason routine antenatal blood pressure and urine checks matter. The condition is often mild, but it can sometimes become serious, so suspected or diagnosed pre-eclampsia needs assessment and ongoing care from a maternity team.

What is pre-eclampsia?

Pre-eclampsia is a condition linked to the placenta that can affect both the pregnant person and the baby.

High blood pressure is a key feature. Protein in the urine can also be present, but RCOG explains that pre-eclampsia can sometimes affect the liver, kidneys or blood clotting without protein being found in the urine.

The exact cause is not fully understood. Pre-eclampsia can happen in any pregnancy, although some people have a higher chance of developing it because of their medical history or other risk factors.

It is not something you can diagnose from symptoms alone. Blood pressure measurements, urine testing and, when needed, further hospital assessment help healthcare professionals determine what is happening.

What are the symptoms of pre-eclampsia?

Pre-eclampsia often causes no noticeable symptoms at first. High blood pressure and protein in the urine may be picked up during a routine antenatal appointment before you feel unwell.

When symptoms do occur, NHS and RCOG guidance says they can include:

a severe headache that does not go away
blurred vision, flashing lights or other vision problems
severe pain below the ribs
sudden or rapidly increasing swelling of the face, hands or feet
vomiting
persistent heartburn that does not improve with usual heartburn medicines
feeling very unwell

These symptoms need immediate medical assessment.

Some of them can occur for other reasons during pregnancy, but that is not something you need to work out yourself. Contact your maternity team so they can assess you properly.

How is pre-eclampsia detected?

Routine antenatal appointments play an important part in detecting pre-eclampsia because early signs may not be noticeable.

Your blood pressure is checked during pregnancy, and your urine may be tested for protein. If your midwife or doctor suspects pre-eclampsia, the NHS says you will usually be referred for further assessment.

Additional checks can include blood tests to assess areas such as liver and kidney function and ultrasound scans to monitor your baby’s growth and wellbeing.

NICE guidance also covers the use of placental growth factor based testing in some people with suspected preterm pre-eclampsia. Your healthcare team will decide which investigations are appropriate in your individual circumstances.

Who has a higher chance of developing pre-eclampsia?

Pre-eclampsia can happen without an obvious reason, but certain factors are associated with a higher risk.

NICE and RCOG identify higher-risk factors that include:

having had high blood pressure before pregnancy
having had high blood pressure or pre-eclampsia in a previous pregnancy
chronic kidney disease
type 1 or type 2 diabetes
certain autoimmune conditions, including systemic lupus erythematosus or antiphospholipid syndrome

Other factors can also contribute to a person’s overall risk, including a first pregnancy, being aged 40 or over, carrying more than one baby, a family history of pre-eclampsia, a long interval since a previous pregnancy and a higher body mass index before pregnancy.

Risk factors are not a prediction. Some people with them will never develop pre-eclampsia, while the condition can occur in people who do not expect to be at increased risk.

Your midwife or doctor should assess your individual risk during antenatal care and discuss any recommended preventative treatment with you. Do not start aspirin or supplements specifically to prevent pre-eclampsia unless a healthcare professional has advised you to do so.

What happens if you are diagnosed with pre-eclampsia?

Care depends on factors such as your blood pressure, blood and urine test results, how many weeks pregnant you are and how your baby is doing.

You may need frequent blood pressure checks and regular blood tests. Ultrasound scans may be used to monitor your baby’s growth and wellbeing.

Some people can be monitored as outpatients, while others need admission to hospital. Severe pre-eclampsia requires hospital care and specialist monitoring.

Medication may be recommended to control high blood pressure. In more severe cases, other medicines may be used as part of specialist treatment. Your maternity team will decide what is appropriate for your circumstances.

Do not start, stop or change medication because of information you have read online. If you are worried about a medicine you have been prescribed, speak to your midwife, obstetrician, GP or pharmacist.

How can pre-eclampsia affect the baby?

Pre-eclampsia can affect how well the placenta works. This may affect the baby’s growth and wellbeing.

Your maternity team may therefore offer additional ultrasound scans and other monitoring. If there are concerns about you or your baby, your healthcare team may discuss whether birth needs to happen earlier than originally expected.

An earlier birth is not necessary in every case. Decisions about timing and method of birth depend on the severity of the condition, your stage of pregnancy and the health of you and your baby.

Your team should explain the reasons for any recommendation and discuss your options with you.

Can pre-eclampsia become serious?

Most cases are not severe, but pre-eclampsia can sometimes lead to serious complications.

The NHS lists possible complications including eclampsia, which involves seizures, HELLP syndrome, stroke, problems with the baby’s growth, premature birth and, rarely, stillbirth.

This is why healthcare professionals monitor the condition closely rather than waiting for someone to feel unwell.

Severe complications are not inevitable after a diagnosis. Your individual situation, test results and response to care all matter.

Pre-eclampsia after birth

Giving birth does not mean monitoring can stop immediately.

Pre-eclampsia can develop for the first time in the days or weeks after a baby is born. People who have already been diagnosed can also experience complications after birth and may need continued blood pressure monitoring and medication.

RCOG recommends follow-up after pre-eclampsia, including a postnatal review. Having had the condition is also associated with a higher risk of high blood pressure, stroke and heart disease later in life, so longer-term follow-up with healthcare professionals matters.

If you experience possible warning symptoms after birth, seek medical assessment even if your pregnancy itself was uncomplicated.

When to get professional advice

Get urgent medical help if you are pregnant or have given birth in the last few weeks and develop symptoms that could indicate pre-eclampsia, including:

a severe headache that does not go away
blurred vision, flashing lights or another sudden change in vision
severe pain below your ribs
sudden or rapidly increasing swelling of your face, hands or feet
vomiting
persistent heartburn that does not improve with usual heartburn medicines
feeling very unwell

If you are pregnant and have your maternity unit’s contact details, call the unit immediately. If you have recently given birth, cannot contact your maternity unit or are unsure where to get help, contact NHS 111.

Call 999 if there is a life-threatening emergency.

You should also contact your maternity team if you are worried about your baby’s movements or have another concern about your health or your baby’s health. You do not need to wait until symptoms become severe before asking for advice.