The chance of a potentially fatal pregnancy condition is increased 41 per cent by IVF, 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.
Around six women and several hundred babies die every year in the UK from complications caused by pre-eclampsia.
The researchers, who are presenting their findings at the American Society for Reproductive Medicine conference in Orlando, suggest that exposing embryos to in vitro culture could produce subtle changes which lead to poor development of the placenta and its blood supply.
This in turn increases the risk of pre-eclampsia.
The researchers controlled for other factors likely to influence the results, such as the women’s age.
Charles Kingsland, a consultant gynaecologist at the Liverpool Women’s Hospital and member of the British Fertility Society, said the findings were interesting, adding: “We are aware as obstetricians that IVF pregnancies bring with them their own risks.”