Recurrence risks for common complications of pregnancy--a review.

A review of the literature concerning the more common complications of pregnancy indicates that recurrence risks are available for most and can be summarized as follows: hydatidiform mole--1.3 to 2.9 per cent; recurrent miscarriage--20 to 30 per cent; ectopic pregnancy--20 to 30 per cent; severe preeclampsia--7.5 per cent; mild preeclampsia--29 per cent; preterm labor--15 per cent after one and 30 per cent after two. While recognizing that each individual case merits full investigation and careful assessment, it is proposed that these risk figures provide a useful basis for use in pre- and postpregnancy counseling.