Pre-eclampsia

Pre-eclampsia occurs after the 20^th week of pregnancy. It is caused by high blood pressure and abnormally high levels of protein in the mother’s urine.

This is a serious condition which affects both the unborn baby and the mother and can only be ‘cured’ by inducing delivery of the baby.

Pre-eclampsia is used as an umbrella term to encompass a range of symptoms. It affects 1 in 5 women during pregnancy who have high blood pressure.

(Source: Patient UK)

Causes of pre-eclampsia

There are several causes which include:

• High blood pressure (often the main cause)
• Kidney problems
• Liver problems
• Obesity
• Migraine
• Age (at higher risk if under 20 or over 40)
• Vitamin deficiency
• Diabetes
• Autoimmune system disorder, e.g. lupus
• Problems with the placenta, e.g. is not fully implanted in the womb
• Pregnant with multiple babies (e.g. twins)

If a woman has experienced pre-eclampsia in a previous pregnancy then she is at high risk of doing so again.

Symptoms of pre-eclampsia

The two main symptoms are:

• High blood pressure
• High levels of protein in the urine

These are the early warning signs of pre-eclampsia.

This condition becomes progressively worse which results in the following symptoms:

• Severe pain in the upper abdomen
• Severe headaches
• Fluid retention which also causes weight gain
• Vomiting
• Blurred vision
• A general feeling of being unwell

These symptoms can be mistaken for other medical conditions such as gallbladder disease or chronic kidney disease so it is important to obtain an accurate diagnosis.

Risk to the unborn baby

Pre-eclampsia is dangerous for the mother but is equally problematic for the unborn baby. It can cause low birth weight which means that the unborn baby is slower to develop than normal.

The reason for this is that blood supply is restricted through the placenta which means that the baby does not receive enough nutrients and oxygen which are vital for its development.

The medical term for this is ‘intra-uterine growth restriction’.

Pre-eclampsia can be detected during a routine ante-natal appointment. If it is present then action will be taken which includes regular urine and blood pressure tests.

Complications of pre-eclampsia

If pre-eclampsia is not treated or monitored then complications will develop. These are extremely serious and can be fatal for either the mother or baby.

They include:

• Seizures known as ‘eclampsia’ (it is important not to confuse the two). These are convulsions which cause fits and a loss of consciousness.
• HELLP syndrome: a blood clotting and liver disorder which is as serious as pre-eclampsia.
• Kidney failure: unable to filter waste products from the blood
• Liver failure: unable to remove toxins or produce bile
• Cerebral haemorrhage: the common name for this is a stroke
• Pulmonary oedema: build up of fluid in your lungs

There is also the risk of developing chronic high blood pressure. Some women find that they develop high blood pressure during their pregnancy but this usually disappears several weeks after birth.

But, other women find that they develop high blood pressure later on in life which may be due to pre-eclampsia.

Treatment for pre-eclampsia

The only treatment for this condition is delivery of the baby. But treatment will also involve reducing the woman’s high blood pressure until the baby has been delivered.

If you are diagnosed with pre-eclampsia then you will be referred for tests and monitored carefully throughout the rest of your pregnancy.

If you have severe symptoms of pre-eclampsia then you will be admitted to hospital. Once there you and your baby will be monitored using the following methods:

• Ultrasound scans
• Blood pressure checks
• Urine samples
• Blood tests

The treatment will include bed rest and high blood pressure medication such as a calcium channel blocker to help lower it.

You may be given anticonvulsant medication and/or an injection of magnesium sulphate to prevent the risk of seizures due to eclampsia.

If your condition is serious enough then your baby will be delivered as soon as possible although this may result in a premature birth. There are risks doing this but these are far outweighed by the complications of severe pre-eclampsia.

Can pre-eclampsia be prevented?

No but it can monitored very carefully if detected early enough. This is why it is important to attend all your ante-natal appointments as any problems such as this will be found.

An ante-natal appointment will involve taking your blood pressure and a sample of urine which is useful for detecting this condition. If you have signs of pre-eclampsia then your midwife will take a keen interest in these and arrange for you to be monitored during the rest of your pregnancy.

You will also be given medication to lower your high blood pressure and advice about a few lifestyle changes. These will include reducing your salt intake, staying physically active as much as possible and avoiding alcohol.

Pre-eclampsia occurs during pregnancy, often as a result of pre-existing high blood pressure -known as ‘primary hypertension’. This means that the mother has high blood pressure before she became pregnant.

But there are cases where the mother suddenly develops high blood pressure during her pregnancy. This is known as ‘gestational hypertension’ which is discussed further in the next section.