High blood pressure and pre-eclampsia in pregnancy: signs, checks and treatment

Your blood pressure is checked at almost every antenatal appointment for a reason. High blood pressure can be the first sign of pre-eclampsia, which is rare but needs treating. Here’s what to know and when to call.

What is pre-eclampsia?

Pre-eclampsia is a condition that can develop in pregnancy. Its early signs are high blood pressure and protein in your urine. The NHS says you’re unlikely to notice these yourself, which is why you have regular blood pressure and urine checks. See urine tests and blood pressure checks in pregnancy.

Symptoms to act on

The NHS lists these as possible symptoms. Any of them can be serious and need to be checked immediately:

a severe headache that does not go away with simple painkillers
vision problems, such as blurred vision or seeing flashing lights
pain below the ribs
sudden swelling of the face, hands or feet
feeling very unwell
heartburn that does not go away with heartburn medicines
being sick

If you’re pregnant and have any of these, call your maternity unit. If you’ve recently given birth, or you can’t reach your maternity unit, call NHS 111. As general emergency advice, call 999 if you think your life or your baby’s is in danger.

Who is more likely to get it?

The NHS lists these as higher-risk situations: diabetes, high blood pressure, kidney disease, an autoimmune condition such as lupus, or pre-eclampsia in an earlier pregnancy. Other risk factors include a first pregnancy, being 40 or over, a Black or South Asian family background, a multiple pregnancy (see twin pregnancy), a close relative who had pre-eclampsia, 10 or more years since your last pregnancy, and a BMI of 35 or more before pregnancy. Having a risk factor doesn’t mean you will get it.

Aspirin

If your midwife or doctor thinks you’re at higher risk, they may recommend a daily low-dose aspirin from week 12 until your baby is born, and calcium supplements if your diet is low in calcium. The NHS says not to start either unless a midwife or GP has told you to.

What happens if you’re diagnosed?

The NHS says there is currently no cure for pre-eclampsia, and treatment focuses on managing it. You’ll usually be referred to hospital for blood tests and scans to check your baby’s growth, then have a care plan with more frequent appointments. Medicine to lower your blood pressure is usually prescribed, and severe cases may need hospital care.

Having your baby earlier is often safer, sometimes before 37 weeks, either by induction or caesarean section. See growth scans in pregnancy.

After the birth

Symptoms usually go away after your baby is born, but sometimes they continue. You may need blood pressure medicine for a few weeks and regular checks. The NHS also says pre-eclampsia can develop in the days or weeks after birth, so keep acting on the symptoms above after your baby arrives.

Questions people ask

Can I prevent pre-eclampsia?

Not completely. If you’re at higher risk, aspirin may be recommended. The NHS says to start it only if a midwife or GP advises you to.

Is swelling a sign of pre-eclampsia?

Sudden swelling is on the NHS list of symptoms to check. Some swelling in pregnancy is common, so mention any sudden or severe change to your midwife.

Does high blood pressure always mean pre-eclampsia?

No. High blood pressure can have other causes, which is why you’ll have your blood pressure and urine checked, and sometimes blood tests, to find out.

Will I have a caesarean?

Not necessarily. The NHS says labour may be induced or a caesarean offered, depending on your situation. Your team will talk through the choices.