Risk of Breast Cancer Associated with Reproductive and Fertility Factors According to a Family History of Breast Cancer
Abstract
Early age at menarche, nulliparity, late age at first birth, and late age at menopause have been consistently associated with an increased risk of breast cancer. The association of these factors in addition to other reproductive and fertility factors with risk of breast cancer is less well characterized in women with a family history of breast cancer. The scope of this research is to examine the association of reproductive and fertility factors with risk of breast cancer among sisters, daughters, granddaughters, and nieces of 426 breast cancer probands as well as women who married into the 426 families. We found that women who have used oral contraceptives and also have a first-degree relative with breast cancer were at significantly increased risk of breast cancer compared to genetically comparable women who never used oral contraceptives. The association was particularly strong in families with multiple cases of breast and ovarian cancer and for oral contraceptive use before 1975. Further follow-up is needed of younger women who used oral contraceptives after 1975. These findings are very important in light of the published recommendations that women with a hereditary predisposition to breast and ovarian cancer take oral contraceptives to lower risk of ovarian cancer.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1999
- Accession Number
- ADB262292
Entities
People
- Dawn Grabrick
- Thomas Sellers