Hearing about pre-eclampsia can feel worrying, but knowing what it is and how it is managed can make it feel less overwhelming. Pre-eclampsia usually develops after 20 weeks of pregnancy, when blood pressure becomes raised and there are signs that organs such as the kidneys or liver may be affected. It can be serious, but with regular antenatal care, early detection, and prompt treatment, many parents and babies do well.

This blog is for information only and does not replace advice from your own midwife or doctor.

What Pre-Eclampsia Is

Pre-eclampsia is a pregnancy-related high blood pressure condition. It is usually diagnosed when someone has high blood pressure (from around 140/90 or higher) together with protein in their urine, which is a sign the kidneys are under strain. It most often develops from 20 weeks of pregnancy onwards, but it can also appear during labour or in the days and weeks after birth. You can read more on the NHS website.

Globally, pre-eclampsia affects an estimated 3 to 8 percent of pregnancies and is one of the leading causes of serious complications in pregnancy, which is why careful monitoring matters, according to the World Health Organization.

What Causes It

The exact cause is not fully understood. Current evidence links it to the way the placenta, the organ that provides oxygen and nutrients to your baby, develops and how blood vessels supply it. When the placenta does not get the blood flow it needs, substances can be released into your bloodstream that affect blood vessels and contribute to high blood pressure and organ stress. There is more on what causes pre-eclampsia on the NHS website.

Importantly, pre-eclampsia is not your fault. Nothing you did or did not do has caused it.

Symptoms And Warning Signs

Early pre-eclampsia may not cause any symptoms you would notice, which is why routine antenatal checks are so important. At your appointments, your blood pressure and urine are checked regularly to pick up early changes.

More noticeable symptoms can include:

A severe headache that does not go away with simple pain relief
Vision changes, such as blurred vision or seeing flashing lights
Pain just below the ribs, often on the right side
Sudden swelling of the face, hands, or feet
Feeling very unwell, or a sense that something is wrong
Heartburn that does not improve with usual remedies
Nausea or vomiting in later pregnancy

Pre-eclampsia can also develop or continue after birth, so it is worth staying aware of these symptoms in the first days and weeks postpartum as well.

Who Is At Higher Risk

Pre-eclampsia can happen to anyone, even with no risk factors. However, some things are known to increase the chances, including:

Having high blood pressure, kidney disease, diabetes, or certain autoimmune conditions
Having had pre-eclampsia in a previous pregnancy
It being your first pregnancy
Being aged 40 or over
Having a body mass index (BMI) of 35 or more at the start of pregnancy
Expecting twins or more
Having a close relative, such as a mother or sister, who had pre-eclampsia

If you are considered at higher risk, your midwife or doctor may suggest additional monitoring and sometimes low-dose aspirin and/or calcium supplements during pregnancy to help reduce the risk. These should only be started on the advice of your healthcare team.

How It Is Diagnosed

Pre-eclampsia is usually picked up through routine antenatal care. Diagnosis typically involves:

Regular blood pressure checks
Urine tests to look for protein
Blood tests to check organ function
Ultrasound scans to assess your baby's growth and the fluid around them

In some hospitals, additional blood tests such as placental growth factor (PlGF) tests may be used to help assess the likelihood of pre-eclampsia. If pre-eclampsia is suspected, you will usually be referred to hospital for closer monitoring and a personalised plan.

Treatment And Management

There is currently no cure for pre-eclampsia apart from delivering the baby and placenta. However, treatment can help manage symptoms and reduce the risk of complications while you and your baby are monitored. Management might include:

Blood pressure medicines to reduce the risk of complications such as stroke
Regular blood and urine tests
Monitoring your baby's growth and wellbeing with scans and heart rate checks
Staying in hospital for observation if your team feels it is safer

The timing of birth depends on how severe the pre-eclampsia is, how stable your blood pressure and blood tests are, and how your baby is doing. Sometimes the safest option is to plan an earlier birth, either by induction of labour or caesarean, especially if the condition is becoming more severe or you are near term.

After your baby is born, blood pressure and symptoms usually improve, but you may need to stay in hospital for a while and continue blood pressure medication and checks at home for a few weeks.

When To Seek Urgent Help

Contact your maternity unit, triage line, GP, or NHS 111 urgently, or call 999 in an emergency, if you are pregnant or have recently given birth and you notice:

A severe or persistent headache
Visual disturbances such as blurred vision, flashing lights, or spots
Pain under your ribs or in your upper abdomen
Sudden swelling of your face, hands, or around your eyes
Sudden swelling in your legs or feet that feels unusual for you
Feeling very unwell, breathless, or confused

Trust your instincts. If something feels wrong, it is always better to get checked, and you are never wasting anyone's time by asking for help.

How It Can Affect Pregnancy And Birth

In many cases, pre-eclampsia is mild and, with monitoring, parents go on to have healthy babies. Occasionally it can lead to complications such as slower growth for the baby, the need to plan an earlier (premature) birth, or more serious problems such as eclampsia (seizures), HELLP syndrome, or issues with the placenta.

Your team will weigh the benefits of continuing the pregnancy, to give your baby more time to grow, against the risks of the condition worsening. This can feel like a lot to process, so it is absolutely okay to ask for explanations more than once and to take time over decisions. Afterwards, you may be offered follow-up appointments to talk through what happened and to check your longer-term heart and blood pressure health. The NCT has more information on high blood pressure, pre-eclampsia, and HELLP.

Can It Be Prevented?

There is no guaranteed way to prevent pre-eclampsia, but some steps can reduce the risk in certain situations. Recommendations from organisations such as the NHS and WHO include:

Low-dose aspirin in pregnancy for those at higher risk (only on medical advice)
Calcium supplements where dietary calcium intake is low (again, on medical advice)
Managing existing conditions such as high blood pressure or diabetes before and during pregnancy
Attending all antenatal appointments so early changes can be picked up

Healthy lifestyle choices, such as not smoking, keeping active within what is safe for you, and eating a balanced diet, support overall pregnancy health, though they cannot fully prevent pre-eclampsia.

The Importance Of Antenatal Care

One of the most powerful tools we have against pre-eclampsia is regular antenatal care. Routine blood pressure and urine checks are designed specifically to catch conditions like pre-eclampsia early, often before symptoms become severe. If you ever feel unsure, worried about symptoms, or confused about test results, please speak up. Your questions are valid, and your healthcare team is there to support you.

Charities such as Tommy's also offer information and a free midwife helpline if you would like extra reassurance or support.

Pre-eclampsia can feel frightening, but you are not alone. With early detection, careful monitoring, and timely treatment, outcomes for many parents and babies are good.

Pre-Eclampsia in Pregnancy