May 29, 2024


Norwegian researchers say that there is a five-fold increase in risk of a dangerous complication of pregnancy in women who have conceived a child through IVF. In a study of 845,300 pregnancies they found that the risk of placenta praevia, a condition in which the placenta covers part or all of the cervix, blocking a baby’s passage into the birth canal, rose from about 3 in 1,000 for normal pregnancies to 16 in 1,000 for IVF pregnancies. And for women who had two pregnancies, one natural and one using reproductive technology, the risk rose three-fold, from 7 in 1,000 to 20 in 1,000.

The cause of the increased risk for the potentially fatal condition is not clear. IVF may trigger contractions which lead to embryos implanting lower down the uterus than in natural conceptions. Or doctors may position the embryo lower down in order to improve implantation rates. The researchers, from St Olav’s University Hospital in Trondheim, suggest that IVF clinics should record the position of every embryo they implant.