Pre-eclampsia

Pre-eclampsia meaning

Pre-eclampsia is a condition where you have high blood pressure (hypertension) in pregnancy and lose too much protein from your kidneys into your urine.

Pre-eclampsia usually comes on some time after the 20th week of your pregnancy and is usually gone within six weeks of you giving birth.

Pre-eclampsia can cause complications for the mother and baby. The more severe the condition becomes, the greater the risk that complications will develop.

The only way to cure pre-eclampsia is by giving birth to (delivering) your baby, but the condition can sometimes be stabilised to allow your pregnancy to progress further. Medication may help prevent complications of pre-eclampsia.

Pre-eclampsia is NOT the same as high blood pressure in pregnancy. Many pregnant women develop mild high blood pressure (hypertension), without protein in their urine. This is known as gestational high blood pressure, or pregnancy-induced high blood pressure.

There is a separate leaflet called High blood pressure in pregnancy.

Pre-eclampsia symptoms and signs

You may have no symptoms to begin with, particularly if you only have mildly raised blood pressure and a small amount of protein in your urine. Pre-eclampsia can become severe with no symptoms developing; this is why blood pressure is checked at every appointment and the urine is always dipped for protein.

If pre-eclampsia becomes worse, one or more of the following symptoms may develop. See a doctor or midwife urgently if any of these occur:

• Severe headaches that do not settle with simple painkillers.

• Problems with your vision, such as blurring or flashing lights.

• Heartburn that doesn't go away with antacids.

• Tummy (abdominal) pain. The pain that occurs with pre-eclampsia tends to be mainly in the upper part of your abdomen, just below your ribs, and just to the right.

• Being sick (vomiting) later in pregnancy (not the morning sickness of early pregnancy).

• Rapidly increasing swelling (puffiness) of your hands, face or feet.

• Not being able to feel your baby move as much.

• Feeling unwell.

Note: swelling or puffiness (oedema) of your feet, face, or hands is common in normal pregnancy. Most women with this symptom do not have pre-eclampsia but it tends to become worse in pre-eclampsia. You should report any sudden worsening of swelling of the hands, face or feet promptly to your doctor or midwife.

Rarely, pre-eclampsia and eclampsia can both develop for the first time up to four weeks after you have given birth. This means that should look out for any of the symptoms above after you give birth and report them to your doctor or midwife. This is called post natal pre-eclampsia.

HELLP syndrome

• HELLP syndrome is a complication which occurs in women who have severe pre-eclampsia or eclampsia.

• It commonly occurs between 27 and 37 weeks of pregnancy but can occur any time from 20 weeks.

• One in three cases occur just after the baby is born.

• In addition to high blood pressure (hypertension) and protein leakage, HELLP syndrome causes problems with the liver, blood cells and clotting disorders.

HELLP stands for 'Haemolysis, Elevated Liver enzymes and Low Platelets', which are some of the medical features of this condition. 'Haemolysis' means that your blood cells start to break down. 'Elevated liver enzymes' means that your liver is affected. 'Low platelets' means that the number of platelets in your blood is low and you are at risk of serious bleeding problems.

It is not certain whether HELLP syndrome is a severe form of pre-eclampsia, or whether it is a different but overlapping disease. HELLP syndrome can occur after pre-eclampsia has been diagnosed, or it may be the first warning of pre-eclampsia. Like pre-eclampsia, it can lead to eclampsia.

Symptoms HELLP syndrome

HELLP syndrome tends to come on quickly but there may be no symptoms. It can cause similar symptoms to pre-eclampsia.

• Headaches are common, and some women experience visual symptoms.

Other symptoms include:

• Feeling unwell,

• Tiredness.

• Pain at the top of the tummy, pain just below the ribs or over the liver area.

• Feeling sick (nausea).

• Being sick (vomiting).

• Feeling fluey.

Symptoms tend to be worse at night.

• You may have easy bruising or purple spots on the skin.

• Your liver may become swollen and tender.

You are more likely to develop HELLP syndrome if:

• You are aged over 35 years.

• Having your first baby.

• Have a multiple pregnancy.

• Have had HELLP syndrome before.

• Have antiphospholipid syndrome.

• It is more common in white women.

Usually the condition resolves fairly soon after your baby is delivered but in about one in three women with HELLP syndrome the condition begins straight after delivery.

HELLP syndrome is an emergency. Doctors need to lower your blood pressure and start you on medicine to reduce your risk of developing eclampsia. Transfusions and plasma exchange can be needed.

The problems caused by HELLP syndrome include clotting problems (1 in 2-20), eclampsia (1 in 20), placental abruption (1 in 5-10 cases) and slow growth in the baby (2 out of 3 cases). In extreme but rare cases, liver failure can occur and transplant is needed. HELLP syndrome can (very rarely) be fatal for mother and baby.

Eclampsia

Eclampsia is a type of fit (a seizure or convulsion) which is a life-threatening complication of pregnancy. Fewer than 1 in 100 women with pre-eclampsia develop eclampsia. Almost half of eclampsia seizures occur after delivery, and about 1 in 5 occur during delivery.

Causes

These conditions seem to begin when the mother's blood vessels (particularly in the kidney) become leaky and possibly inflamed, in response to a trigger which we believe comes from the afterbirth (placenta).

The placenta connects a mother to her unborn baby, and the baby receives oxygen and nutrients through it. It's thought that the development of the blood vessels of the placenta is different in women who develop pre-eclampsia, and that in these women the placenta may not attach as effectively to the wall of the womb (uterus). This is assumed to trigger the release of substances that then affect the mother's blood vessels.

There is a genetic component to pre-eclampsia, HELLP syndrome and eclampsia - this might be to do with the genetics of mother or of the baby (and the placenta). You are more likely to develop pre-eclampsia if your mother and sisters had it, but also more likely to develop it if the baby's father's mother had it when pregnant with him. These conditions are also more common if you are having twins or more, and in a condition called hydatidiform mole, when abnormal placental tissue forms in the womb.

Can pre-eclampsia be prevented?

The National Institute for Health and Care Excellence (NICE) recommends that women at increased risk of developing pre-eclampsia should take low-dose aspirin.

NICE recommends 75-150 mg aspirin every day from 12 weeks of your pregnancy until the birth of your baby.

Diagnosis

Pre-eclampsia. This is diagnosed if:

• Your blood pressure becomes high; and

• You have an abnormal amount of protein in your urine, initially detected with a dipstick in the surgery but usually confirmed on collecting a larger sample, sometimes over 24 hours.

HELLP syndrome. This is diagnosed if:

• You have symptoms and signs of pre-eclampsia, particularly feeling unwell with tummy pain, feeling sick (nausea) and being sick (vomiting), or headache; and

• You have abnormalities on blood tests, suggesting the blood and liver changes of HELLP syndrome.

Eclampsia. This is diagnosed if:

• You have symptoms and signs of pre-eclampsia or HELLP syndrome; and

• You develop fits or convulsions.

Complications

Most women with pre-eclampsia or HELLP syndrome do not develop serious complications. The risk of complications increases the more severe the pre-eclampsia becomes. The risk of complications is reduced if pre-eclampsia is diagnosed early and treated. A rare but serious complication is disseminated intravascular coagulation, which can occur if a woman has had to have many blood transfusions.

For the mother

Serious complications are uncommon but include the following:

• Eclampsia.

• Liver, kidney and lung problems.

• A blood clotting disorder.

• Bleeding into the brain (a stroke).

• Severe bleeding from the afterbirth (placenta).

For the baby

The poor blood supply in the placenta can reduce the amount of food and oxygen reaching the growing baby. On average, babies of mothers with pre-eclampsia tend to be smaller. There is an increased risk of premature birth and of stillbirth. Babies of mothers with pre-eclampsia are also more likely to develop breathing problems after they are born.

What are the possible complications of eclampsia?

The complications of eclampsia are severe for mother and baby. They include an increased level of the risks of pre-eclampsia, and a risk of a type of placental bleed called placental abruption - when the placenta starts to shear off the wall of the uterus (womb).

Treatment

• Your care will be supervised by a specialist obstetrician.

• Regular tests of blood pressure and protein in the urine will be done.

• Your baby's heart rate and growth will be monitored.

• Depending on the severity of pre-eclampsia, you may be admitted to hospital; this is more likely with severe pre-eclampsia or HELLP.

• The only cure is delivery of the baby - the timing of this will balance your health, the health of your baby inside your uterus (as pre-eclampsia can restrict growth), and the risks to your baby from delivering them early. Delivery is ideally done after 34 weeks, unless waiting this long is thought to be unsafe.

• You may be given medicine to reduce your blood pressure, reduce your risk of eclampsia (fits) and to make your baby's lungs more mature, if early delivery is being planned. If you have eclampsia, you will be given medication into a vein to stop the fit and the baby will be delivered as soon as possible, usually be caesarean section.

What happens after my baby is born?

Pre-eclampsia usually settles down soon after birth. More severe pre-eclampsia can still cause complications during the first few days (including eclampsia and HELLP syndrome) and you will continue to be monitored closely.

You may need to continue taking medication to lower your blood pressure for several weeks and you may need to stay in hospital for several days. You should see your GP 6-8 weeks after birth for a blood pressure and urine check. If you had severe pre-eclampsia or eclampsia, you should also have a follow-up appointment with your obstetrician to discuss your case, and give advice for future pregnancies.

For a few women, high blood pressure and protein in the urine have not completely settled by six weeks. If this is the case, they will be referred to a specialist.

Will my long-term health be affected?

Some research has shown that women who develop these conditions may have a slightly higher chance of developing:

• High blood pressure (hypertension).

• Have a higher chance of having a heart attack or stroke in the future.

However, the overall risk of developing these problems is still low. Therefore, you may wish to look at ways in which you may be able to reduce your risk of these complications by making changes to your lifestyle.

These can include avoiding some combined hormonal contraceptive pills in the future, and keeping to:

• A healthy weight.

• Exercising regularly.

• Eating a healthy, balanced diet.

• Not smoking.

See the separate leaflet called Cardiovascular disease (Atheroma).

If you have had pre-eclampsia, HELLP syndrome or eclampsia during your pregnancy, it is important that your blood pressure be checked several times after you leave hospital after you have given birth. This will usually be done by a midwife who visits you at home. Your blood pressure will also be checked and your urine checked for protein, at your six- to eight-week check, to make sure that things have returned to normal.

What is my risk of developing pre-eclampsia, HELLP syndrome or eclampsia again in a future pregnancy?

The risks of pre-eclampsia in a future pregnancy are one in three if your baby was born between 28-34 weeks of gestation, one in four if born between 34-37 weeks, and one in six if born after 37 weeks. If you have gestational hypertension, but not pre-eclampsia, your future risk of gestational hypertension is up to one in eight, and your future risk of pre-eclampsia is up to one in nine.

Being obese is a risk factor for pre-eclampsia (see above). If you have had pre-eclampsia in a previous pregnancy and you are planning for another pregnancy but you are overweight or obese, you should try to lose weight before you become pregnant again. This may help to reduce your chance of developing pre-eclampsia in your next pregnancy.

How common are pre-eclampsia, eclampsia and HELLP syndrome?

• Pre-eclampsia affects around 4 in every 100 first pregnancies and 2 in every 100 second or subsequent pregnancies.

• HELLP syndrome also occurs in 2 per 100,000 pregnancies.

• Eclampsia complicates 2.7 per 10,000 births.

• Deaths (of mothers) from eclampsia and pre-eclampsia are very rare - in 2019-2021 there were nine maternal deaths from these conditions in the UK and Ireland.

Who is at risk of pre-eclampsia, eclampsia and HELLP syndrome?

Any pregnant woman can develop these conditions. You have an increased risk, compared to the average risk, if:

Moderate risk factors

• This is your first pregnancy, or it has been over 10 years since your last pregnancy.

• You are aged 40 years or more.

• You have obesity (your BMI is 35 or over).

• You are expecting more than one baby.

High risk factors

• You have had high blood pressure (hypertension) or pre-eclampsia in a previous pregnancy.

• You have diabetes or chronic (persistent) kidney disease.

• You had high blood pressure before the pregnancy started.

• You have antiphospholipid syndrome. (Women with this condition also have an increased risk of having a miscarriage and of developing blood clots.)

• You have systemic lupus erythematosus. (This condition can cause various symptoms, particularly joint pains, skin rashes and tiredness. Problems with kidneys and other organs can occur in severe cases.)

Dr Mary Lowth is an author or the original author of this leaflet.