There are a number of potential risks to women who conceive through in vitro fertilisation (IVF). Among these, ovarian hyperstimulation syndrome and multiple pregnancies are the most serious. Other potential risks include increased levels of anxiety and depression, ovarian torsion, ectopic pregnancy, pre-eclampsia, placenta praevia, placental separation and increased risk of cesarean section. The association between assisted conception and long-term risk of cancer is debatable. The objective of this review is to critically evaluate the current evidence for potential risks to women who conceive through IVF. To assess the relative risk for any condition, a number of factors need to be taken into account including the method used in identifying the study and control group, the women's characteristics and the number of women included in the study. Many conditions such as ectopic pregnancy and pre-eclampsia appear to be commoner in assisted conception than in spontaneous pregnancy. Nevertheless, the increased risk of these conditions is probably related to the woman's subfertility status and/or increased incidence of multiple pregnancy. Currently, all efforts should concentrate on reduction of multiple births from IVF by restricting the number of transferred embryos.