Breast cancer risk of hormonal contraception: Counselling considering new evidence

The possibility that the use of hormonal contraceptives may increase the risk of breast cancer has been raised since many years. In the past this hypothesis has been dismissed on the basis that available data were generally derived from "old" studies in which relatively high hormone doses had been used. The recent publication of two studies that analysed data from women receiving low-dose hormonal contraception and showed a statistically significant increase in breast cancer contradicts this reassuring belief. The topic however is not settled, since different results were obtained in other studies and since hormonal contraception (HC) also has unquestionable positive effects such as a decrease in ovarian and in endometrial cancer. The aim of the present paper is to provide evidence that may help gynaecologists and oncologists in discussing with their patients the use of HC. Even if cancer phobia is a strong reason for not using or limiting HC, patients must be informed that notwithstanding the slightly increased breast cancer risk, the overall cancer risk may still be lower than non-users. Proper counselling may help the woman choose the most suitable contraception in the different phases of her life and on the basis of other conditions that may increase cancer risk such as overweight, smoking or family history.