Pre-eclampsia is a condition that can occur in pregnant women when there is a problem with the placenta (the organ that links the baby’s blood supply to the mother’s). As a result, the mother can develop:
- high blood pressure (hypertension),
- protein in her urine (proteinuria), and
- fluid retention (oedema).
In the unborn baby, pre-eclampsia can cause growth problems (intrauterine growth retardation).
Pre-eclampsia usually occurs during the second half of pregnancy (from around week 20), or immediately after the delivery of a baby. Pre-eclampsia may not be noticeable to the woman who has it, but it will show up during routine antenatal appointments.
In most cases, the symptoms will be monitored with regular blood pressure and urine tests, although some women will need to be admitted to hospital. The only way to prevent pre-eclampsia is to induce labour (start labour artificially) and deliver the baby.
Whether this can be done will depend on how far along the pregnancy is. Being born prematurely (before the 37th week of pregnancy) can be dangerous for the baby, but this may sometimes be necessary to relieve the symptoms in the mother.
How common is pre-eclampsia?
Mild pre-eclampsia can affect up to 10% of first time pregnancies. More severe pre-eclampsia can affect between 1-2% of pregnancies. If you have pre-eclampsia during your first pregnancy, you will be more likely to have it again in any subsequent pregnancies.
While certain factors have been identified that increase the likelihood of pre-eclampsia occurring, such as having a family history of the condition, the cause of pre-eclampsia is still not fully understood.
Outlook
Mild pre-eclampsia can be monitored and will usually disappear soon after the birth. However, in some cases, further complications can develop, such as eclampsia. This is a type of seizure that the mother can have. It is rare, but can be life threatening for both the mother and the baby.
The complications of pre-eclampsia are responsible for the deaths of around six women every year in the UK. Several hundred babies also die each year following complications from severe pre-eclampsia, often as a result of premature birth. Therefore, the earlier that pre-eclampsia is diagnosed and monitored, the better the outlook for both mother and baby.
