Reducing the risk of pre-eclampsia – Information for women taking aspirin in pregnancy

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This leaflet is for women who have been advised to take aspirin during their pregnancy.

What is pre-eclampsia and why have I been advised to take aspirin?

Pre-eclampsia is a condition of pregnancy which typically presents after 20 weeks. It is a combination of high blood pressure (hypertension) and protein in your urine. It can also affect your brain, kidneys, and liver, as well as keep your baby from growing properly. Aspirin has been shown to reduce the risk of developing pre-eclampsia by improving the blood flow through the placenta.

How do I know if I am at risk of pre-eclampsia?

Pre-eclampsia can occur in any pregnancy, but you are at higher chance f you have the following:

High risk factors:

You have High blood pressure before pregnancy (chronic hypertension)
You had High blood pressure or pre-eclampsia in a previous pregnancy
You have Diabetes (Type 1 or Type 2)
You have Chronic kidney problems
You have autoimmune problems such as Systemic Lupus Erythematosus

(SLE). If you require further information, please speak to your midwife.

Moderate risk factors:

This is your first pregnancy
You are aged 40 or older
You have a BMI of 35 or above
Your last pregnancy was more than 10 years ago
You are having twins or triplets
You have a family history of pre-eclampsia (mother or sister)

Taking aspirin

You should take aspirin from 12 weeks in your pregnancy until your baby is born. Take the tablets as advised by your midwife or doctor (150mg) once a day with some food in the evening. If you miss a tablet, take it when you remember. Do not take more than two aspirin tablets in 24 hours. Aspirin is safe in pregnancy and will not harm your baby. You should check with your doctor if you have ever had bleeding from the stomach lining or severe asthma.

Symptoms and signs of pre-eclampsia

Some people with pre-eclampsia may have no symptoms and it may be picked up when your blood pressure and urine are checked during your routine antenatal appointments. Therefore, it is important you attend these appointments. Some people may experience symptoms, and you should present to a maternity unit if these occur.

The symptoms to look out for are:

Severe headaches that do not go away with pain relief (paracetamol)
Blurred vision or flashing lights
New nausea and vomiting
Severe pain in the upper abdomen / under the ribs
Sudden onset of swelling of the face, hands or feet
Generally feeling unwell

These symptoms can be serious, and you should call Maternity Triage which is open 24/7.

How may pre-eclampsia affect my baby?

Pre-eclampsia is caused by the placenta not developing as expected the placenta should bring blood with nutrients and oxygen from mum to baby. If the blood cannot flow through the placenta, then your baby’s growth may be restricted and may need to be born early.

Babies born prematurely may be unwell and need a longer stay in hospital for monitoring.

If I develop pre-eclampsia, how will it be monitored?

If you are diagnosed with pre-eclampsia, your blood pressure and urine will be measured more regularly and you will have regular blood tests. Your baby’s heart rate will be monitored, and you may have ultrasound scans to measure your baby’s growth. Sometimes, you will be asked to stay in the hospital.

If you have any of the symptoms mentioned in this booklet, or your baby’s pattern of movements have changes, you must inform Maternity Triage straight away. If you have any concerns, you can contact Maternity Triage 24/7: 01908 996871

Further information can also be found at Action on Pre-Eclampsia (action-on-preeclampsia.org.uk)

We encourage patients to be involved in their care by:

Being part of the conversation and shared decision making
Asking questions if something is not clear
Speaking up if you have concerns

Checks are there to protect you and you can be part of them. Behave with respect and kindness towards healthcare professionals.

If you have any concerns, you can contact your midwife, GP or the hospital:

Antenatal Day Assessment Unit
Milton Keynes University Hospital
Direct Tel: 01908 996481

Labour Ward, Milton Keynes University Hospital
Direct Tel: 01908 996471
Switchboard Tel: 01908 660033

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