This information is for general guidance only.

It does not replace advice from your midwife, GP or obstetric team. Read more about our approach.

Pre-eclampsia in pregnancy: symptoms, risks and treatment

What is pre-eclampsia?

Pre-eclampsia is a condition that affects some pregnant women, usually from 20 weeks of pregnancy onwards (though rarely earlier). It is characterised by high blood pressure and protein in the urine, and can progress to cause serious complications if not monitored and treated.

Most cases are mild and well managed with appropriate care. Early detection through routine blood pressure checks is one of the most important reasons not to miss your antenatal appointments. Risk is higher in twin pregnancies, and pre-eclampsia sits alongside other pregnancy complications that routine care helps catch early. If you have the urgent symptoms listed above, do not wait for your next appointment, call immediately.

How common is pre-eclampsia?

~6%

of pregnancies are affected by pre-eclampsia

1-2%

affected by severe pre-eclampsia

From 20 weeks

most commonly appears at or after this point

Postnatal

can also develop in the days or weeks after birth

First pregnancy

risk is higher than in subsequent pregnancies

Early signs versus urgent symptoms

Early signs (found at appointments)

  • High blood pressure (hypertension), 140/90 mmHg or above
  • Protein in urine (proteinuria), detected on a urine dip test
  • You usually do not feel anything at this stage
  • This is why antenatal BP and urine checks matter so much

Urgent symptoms — seek help

  • Severe, persistent headache not relieved by paracetamol
  • Vision problems: flashing lights, blurred vision, spots
  • Pain or tenderness below the ribs (epigastric pain)
  • Sudden swelling of face, hands or feet
  • Vomiting that does not stop
  • Feeling very generally unwell

Some swelling of feet and ankles is normal in pregnancy. It is sudden, severe or facial swelling that needs assessment.

Who is at higher risk?

High-risk factors

One of these is usually enough to be offered preventive aspirin.

  • First pregnancy
  • Previous pre-eclampsia
  • Diabetes (type 1 or type 2)
  • Chronic high blood pressure before pregnancy
  • Kidney disease
  • Autoimmune conditions (lupus, antiphospholipid syndrome)
  • Twin or multiple pregnancy

Moderate-risk factors

Two or more of these combined are usually enough to offer aspirin.

  • Age 40 or over
  • BMI of 35 or above before pregnancy
  • Family history of pre-eclampsia (mother or sister)
  • Gap of more than 10 years since previous pregnancy
  • Black or South Asian family background (higher risk in UK data)
  • IVF pregnancy

Preventive aspirin

If you have one high-risk factor, or two or more moderate-risk factors, your midwife should recommend low-dose aspirin (75 to 150mg daily) from week 12 until birth. Do not start aspirin without medical advice, but do ask your midwife about it at your booking appointment if any of these apply to you.

Risk factors and management are outlined in the NHS guidance on pre-eclampsia and the RCOG hypertension in pregnancy guideline.

How is it diagnosed?

At routine antenatal appointments

  • Blood pressure measured at every appointment.
  • Urine dipstick test at every appointment.
  • If either is abnormal, referral to hospital for further assessment.

At hospital

  • Repeat blood pressure measurements
  • Blood tests: full blood count, liver and renal function, clotting (to detect HELLP syndrome)
  • Ultrasound to check the baby's growth and the placenta
  • Doppler scan to measure blood flow through the placenta

Treatment and management

There is no cure for pre-eclampsia other than delivering the baby. The aim of treatment is to manage blood pressure, monitor mother and baby closely, and time delivery appropriately.

Blood pressure medication

  • Labetalol is most commonly used
  • Alternatives include nifedipine or methyldopa
  • All are considered safe in pregnancy
  • Aim: keep blood pressure below 150/100 mmHg

Monitoring

Outpatient monitoring if mild and stable. Hospital admission if severe, rapidly worsening, or if your baby shows signs of distress on CTG or Doppler.

Delivery timing

  • Mild: typically managed until 37 to 38 weeks, then induction or caesarean offered.
  • Severe: delivery may be recommended earlier, sometimes urgently at any gestation.
  • Very preterm: a careful balance managed by a specialist team.

Magnesium sulphate

Given intravenously in hospital to women with severe pre-eclampsia to prevent seizures (eclampsia).

Complications

Most cases are managed safely. These complications are rarer but worth understanding.

HELLP syndrome

A severe variant with red blood cell breakdown, elevated liver enzymes and low platelets. Needs urgent treatment and delivery.

Eclampsia

Seizures caused by pre-eclampsia. Rare in the UK thanks to monitoring. Treated with magnesium sulphate.

Placental abruption

High blood pressure increases the risk of the placenta detaching from the uterus.

Fetal growth restriction

Pre-eclampsia reduces placental blood flow, which can affect baby's growth.

Stroke

Very high blood pressure increases stroke risk. Medication dramatically reduces this.

Pre-eclampsia after birth

Pre-eclampsia can develop for the first time after birth (postpartum pre-eclampsia), most commonly in the first 48 hours but up to 6 weeks after birth. Symptoms are the same as during pregnancy.

Your blood pressure will be checked in hospital after delivery. After discharge, if you develop severe headache, visual disturbance, right upper abdominal pain or sudden swelling, call 999 or go to A&E immediately.

Blood pressure medication may need to continue for several weeks after birth. Always complete the course, even once you feel better.

Long-term health after pre-eclampsia

Pre-eclampsia increases the long-term risk of:

  • Cardiovascular disease (heart disease, stroke)
  • High blood pressure in later life
  • Kidney disease
  • Pre-eclampsia in future pregnancies

Recommended follow-up

  • Annual blood pressure check with your GP
  • Annual urine test for protein
  • Maintain a healthy weight, exercise regularly, and avoid smoking

Action on Pre-eclampsia (APEC) offers information and support for people affected by pre-eclampsia: apec.org.uk | 020 8427 4217.

Related guides and tools

Why antenatal appointments matter→ Gestational diabetes guide→ DVT in pregnancy (shared risk)→ Pre-eclampsia in twin pregnancies→

A note from our team

This guide reflects NHS UK, NICE and Royal College of Obstetricians and Gynaecologists guidance on pre-eclampsia. Your midwife and obstetric team are your best source of advice for your individual pregnancy. Read more about us.

Frequently asked questions

Will pre-eclampsia affect my baby?
It can. Pre-eclampsia reduces blood flow through the placenta, which may affect your baby's growth and, in severe cases, the amount of amniotic fluid. This is why extra monitoring is offered. Most babies are born healthy with appropriate care, though delivery may be recommended earlier than the full due date if pre-eclampsia is severe.
Can pre-eclampsia be prevented?
Not completely, but the risk can be significantly reduced in higher-risk women by taking low-dose aspirin (75 to 150mg daily) from 12 weeks of pregnancy. Your midwife will assess your risk factors at the booking appointment and recommend aspirin if needed. Maintaining a healthy weight and managing any existing blood pressure or diabetes also help.
What is the difference between pre-eclampsia and eclampsia?
Pre-eclampsia is the condition of high blood pressure and protein in the urine during pregnancy. Eclampsia is the rare complication where pre-eclampsia causes seizures. Eclampsia is uncommon in the UK thanks to monitoring and treatment, and magnesium sulphate given in hospital significantly reduces the risk when severe pre-eclampsia is diagnosed.
Can I have a natural birth if I have pre-eclampsia?
Often, yes, particularly if the condition is mild and well controlled. Labour may be induced slightly earlier than your due date. Continuous monitoring will be recommended in labour. If the condition is severe, or your baby needs to be delivered urgently, a caesarean may be recommended instead.
Does pre-eclampsia go away after birth?
For most women, yes, although it can take several weeks. Blood pressure is monitored carefully in hospital after delivery and for the following weeks. Medication may need to continue for a while. Pre-eclampsia can also develop for the first time after birth (postpartum pre-eclampsia), so any warning symptoms in the weeks after delivery need prompt medical attention.
Am I at higher risk in future pregnancies?
Yes. Having had pre-eclampsia increases your risk of it in a future pregnancy, so your next pregnancy will usually be managed as higher risk from the start. Low-dose aspirin from 12 weeks will be offered, and you will have closer monitoring. Most women who have had pre-eclampsia go on to have healthy future pregnancies with appropriate care.
What is HELLP syndrome?
HELLP stands for Haemolysis (red blood cell breakdown), Elevated Liver enzymes, and Low Platelets. It is a severe variant of pre-eclampsia that can develop quickly and needs urgent treatment and delivery. Symptoms can include severe upper abdominal pain, nausea, headache and feeling very unwell. Any of these in late pregnancy or shortly after birth need immediate medical assessment.