How pregnancy reduces breast cancer risk

Scientists from the FMI have identified a molecular mechanism that may explain how early pregnancy reduces the risk for breast cancer. Their Early pregnancy is the best protective agent against breast cancer. Very young mothers are particularly protected: Their lifelong breast cancer risk is cut in more than half when compared to other women. Even though these facts have been known for decades, scientists did not understand why pregnancy could have such an impact later in life. Research conducted by Mohamed Bentires Alj's group at the Friedrich Miescher Institute for Biomedical Research illuminates now some of the molecular and cellular mechanisms responsible for this protective effect. The scientists could show that early pregnancy changes mammary cell fate. By analyzing gene expression profiles of specific subpopulations of the mammary gland, they found that genes involved in differentiation were up-regulated in mice after pregnancy.