Abortion and breast cancer: a hard decision made harder.

Over recent years, concerns have been raised about a possible causal relation between induced abortion and subsequent breast cancer. The abrupt hormonal changes associated with termination of pregnancy may induce changes in breast epithelial cells at a stage when they are not fully differentiated and therefore more vulnerable to later development of breast cancer. This review examines the published evidence supporting and refuting this hypothesis and concludes that there are, to date, insufficient data to justify warning women of future breast-cancer risk when counselling them about abortion.