Overview
Pre-eclampsia is a condition of pregnancy that causes high . It usually begins after 20 weeks and is diagnosed when blood pressure is 140/90 mm Hg or higher together with protein in the urine, a sign that the kidneys are under strain.
In most women it is not severe, but it can become serious for both mother and baby. It can also develop in the days or weeks after the birth. There is no cure, but treatment can keep mother and baby safe, and symptoms usually improve after the birth.
Symptoms
The early signs are high and protein in the urine. A woman rarely notices these herself, which is why they are checked at every antenatal visit. Other symptoms include:
- A severe headache that simple painkillers do not ease
- Blurred vision or flashing lights
- Pain just below the ribs
- Sudden swelling of the face, hands or feet
- Vomiting, or heartburn that does not settle with heartburn medicine
- Feeling very unwell
When to see a doctor
Do not wait for your next appointment, and tell the staff that you are pregnant or have recently had a baby. Also see your midwife or doctor if you have a risk factor, or if your has not been checked at recent visits.
Causes
The cause of pre-eclampsia is not known. Some women are more likely than others to develop it, as the risk factors below show.
Risk factors
- Diabetes, high or kidney disease before pregnancy
- Autoimmune conditions such as lupus
- Pre-eclampsia in an earlier pregnancy
- A first pregnancy
- Age 40 or over
- Twins or more
- A mother or sister who had pre-eclampsia
- Ten years or more since the last pregnancy
- Black or South Asian background
Having a risk factor does not mean you will get pre-eclampsia, but it is a reason for closer care.
Complications
Most cases are not severe. Serious complications are uncommon but can be life threatening:
- Eclampsia, which means fits (seizures) in the mother
- HELLP syndrome, a rare problem affecting the liver and blood
- Stroke, and damage to the kidneys or liver
- For the baby: slow growth in the womb, early birth and stillbirth
- A higher chance of heart disease later in life
Prevention
Pre-eclampsia cannot always be prevented. What helps:
- Going to every antenatal appointment, so your risk can be assessed
- Low-dose aspirin or calcium if you are at higher risk and your doctor or midwife advises it. Do not start either on your own
- Treating existing high
- A healthy diet, regular activity and a healthy weight, which may lower the risk
Diagnosis
Diagnosis starts with and urine checks at antenatal visits. If pre-eclampsia is suspected, you are usually sent to hospital for:
- Blood pressure checks and a urine test for protein
- Blood tests
- scans to check the baby's growth
Treatment
A specialist assesses how severe it is and agrees a plan, with more frequent visits and extra growth scans. Mild cases may be managed at home. More severe cases need a hospital stay until the birth is safe.
- Medicines to lower and reduce the risk of stroke
- Magnesium sulfate, given by injection or drip in severe cases to prevent fits
- Steroid injections to help the baby's lungs mature, if an early birth is expected
- Early birth, by induced labour or caesarean, which is often safest and sometimes happens before 37 weeks
After the birth, mother and baby are watched in hospital. Some women need blood pressure medicine for a short time, with regular checks after going home.
Myths and facts
Things people often say about this. Open each one to see what is true.
Myth“Swelling of the face, hands and feet is just part of pregnancy.”What is true?
Fact
Sudden swelling of the face, hands or feet can be a sign of pre-eclampsia, especially with a headache, vision changes or pain below the ribs. Tell your midwife or doctor straight away rather than waiting for the next visit.
Myth“I feel well, so my blood pressure must be fine.”What is true?
Fact
The early signs, high blood pressure and protein in the urine, are rarely noticed by the woman herself, and some women with pre-eclampsia have no symptoms at all. That is why they are looked for at every antenatal visit.
Myth“A bad headache can be slept off or treated with a painkiller.”What is true?
Fact
A severe headache that does not respond to simple painkillers is one of the warning signs of pre-eclampsia. Contact your maternity unit or go to hospital.
Myth“Once the baby is born, the danger is over.”What is true?
Fact
Pre-eclampsia can start in the days or weeks after the birth, even in women whose blood pressure was normal during pregnancy. Symptoms usually settle after the birth but can carry on, so keep watching for the warning signs and keep any blood pressure checks you are asked to have.
Myth“Pre-eclampsia only happens in a first pregnancy.”What is true?
Fact
A first pregnancy raises the risk, but it can happen in any pregnancy. Pre-eclampsia in an earlier pregnancy, twins, diabetes, high blood pressure, kidney disease and a gap of ten years or more since the last pregnancy also raise it.
Questions to ask your doctor
Tick the ones you want answered and take them with you.
Common questions
Can pre-eclampsia happen after the baby is born?
Yes. It can develop in the days or weeks after the birth, even if your blood pressure was normal in pregnancy. If you have a severe headache, vision changes, pain below the ribs or sudden swelling, contact your maternity unit or go to hospital straight away.
Will my baby have to be born early?
Often early birth is the safest option, sometimes before 37 weeks, but it depends on how severe the condition is, how far along you are and how the baby is doing. Mild cases may be managed with close monitoring at home. Your team will explain the plan.
Could it happen again in another pregnancy?
Pre-eclampsia in an earlier pregnancy raises the chance in a later one. Tell your midwife or doctor early in the next pregnancy so extra care can be planned and they can tell you whether aspirin is right for you.
How can I tell pre-eclampsia from normal pregnancy aches?
You cannot always tell. Headaches, heartburn, vomiting and swelling can all happen in pregnancy, so treat a severe or sudden version of any of them as a reason to be checked. Only a blood pressure and urine test can show whether it is pre-eclampsia.