Increasing parity and age at first full-term pregnancy are established risk factors for breast cancer in the general population. However, their effects among BRCA1 and BRCA2 mutation carriers is still under debate. We used retrospective data on BRCA1 and BRCA2 mutation carriers from the UK to assess the effects of parity-related variables on breast cancer risk.
CR-UK Genetic Epidemiology Unit, Strangeways Research Laboratory, Department of Public Health and Primary Care, Worts Causeway, University of Cambridge, Cambridge, CB1 8RN, UK. antonis@srl.cam.ac.uk