Pre-eclampsia

Pre-eclampsia is a pregnancy complication that affects about 10% of first time mums. It usually happens after 28 weeks gestation and close to the end of the third trimester. If you have pre-eclampsia you will have high blood pressure that causes a headache. You may also have spots in front of your eyes or blurred vision. Some women also get pain at the top of their tummy, which is either central or right sided. Women often worry about swelling in pregnancy as a sign of pre-eclampsia. However, swollen legs are very common in the third trimester especially in hot weather. If you have symptoms of pre-eclampsia and are over 20 weeks pregnant you should have your blood pressure checked and see a doctor.

Pre-eclampsia is caused by the placenta not implanting deeply enough into the lining of the womb at the start of the pregnancy. In those at risk of pre-eclampsia your doctor may recommend taking aspirin from at least 12 weeks of pregnancy until 36 weeks. Women at high risk of pre-eclampsia are those with high blood pressure before pregnancy or in a previous pregnancy, chronic kidney disease and diabetes before pregnancy. Women at moderate risk of pre-eclampsia are those who are first time mums, 40 years or older, obese, with a family history of pre-eclampsia or twin pregnancy.

Pre-eclampsia can be controlled with medication and you will probably be admitted to hospital for close monitoring of you and your baby. Commonly this involves urine tests for protein, blood tests and a daily tracing of your babies heart beat. However, once you develop pre-eclampsia it can only be cured by delivery of your baby and the placenta. This is often by having labour induced from 38 weeks onwards or by caesarean section if you have severe pre-eclampsia between 24 and 34 weeks of pregnancy.

You might wonder how pre-eclampsia affects your baby. Because the placenta is not working properly your baby may be small or stop growing and this requires early delivery. You will be monitored with regular ultrasound scans to check the size and growth of your baby. These can be as frequent as every second day or more commonly they are performed every two weeks.

If you have pre-eclampsia there is a 16% you will have it in your next pregnancy. If you have severe pre-eclampsia requiring delivery between 28 and 34 weeks the recurrence risk is 25% and if it is severe requiring delivery before 28 weeks the recurrence risk is 50%.