Reproductive factors and risk of contralateral breast cancer by BRCA1 and BRCA2 mutation status: results from the WECARE study Jenny N. PoynterBryan LangholzJoan LargentLene Mellemkjær • Leslie BernsteinKathleen E. MaloneCharles F. LynchAke Borg • Patrick ConcannonSharon N. TeraokaShanyan XueAnh T. Diep • Therese TorngrenColin B. BeggMarinela CapanuRobert W. Haile • The WECARE Study Collaborative GroupJonine L. Bernstein