The present analysis includes data from the five BCSC registries that collect data on HER2 expression status and reproductive history: Group Health (western Washington State), the New Hampshire Mammography Network, the New Mexico Mammography Project, the San Francisco Mammography Registry, and the Vermont Breast Cancer Cited by: Reproductive history and exogenous hormonal exposures are acknowledged risk factors for breast cancer in the general population. In women at increased breast cancer risk for genetic predisposition or positive family history, data regarding these risk factors Cited by:
Reproductive History and Cancer Risk - National Cancer. How does menstrual and reproductive history affect breast cancer risks? - National Breast Cancer Foundation Women who began their menstrual cycles before age 12, or have no biological children, .
Reproductive factors that increase the duration and/or levels of exposure to ovarian hormones, which stimulate cell growth, have been associated with an increase in breast cancer risk.