IVF increases the chance of a potentially fatal pregnancy condition by 41 per cent, research suggests.
Data from six studies found the risk of pre-eclampsia was much higher in IVF pregnancies than among those conceived naturally.
Pre-eclampsia usually occurs from around 20 weeks of pregnancy and can lead to women suffering high blood pressure, protein in the urine and fluid retention.
Experts do not know exactly what causes the condition to develop but it causes issues with the placenta and can lead to growth problems in the baby.
Mild pre-eclampsia can be closely monitored but, in more severe cases, women must be admitted to hospital and may need to be delivered prematurely.
Women can also go on to develop eclampsia, a type of seizure which can be life-threatening for mother and baby.
Around six women and several hundred babies die every year in the UK from complications caused by pre-eclampsia.
In the latest study, experts from US universities and research centres, including the National Institutes of Health, pooled data from six studies.