Differences in Risk Factors for Breast Cancer: Lesbian and Heterosexual Women

Abstract

Purpose/Objectives: To compare differences in risk for developing breast cancer between lesbian and heterosexual women. Design: Retrospective medical record review. Setting: Lyon-Martin Women's Health Services (LMWHS) in San Francisco, California. Sample: Women age 35 or older, seen at LMWHS in 1995, 1996, or 1997, who described themselves as either lesbian or heterosexual. The typical participant (n = 1019) was 42.9 years old (SD = 6.85, range 35–75), white (70%), and employed (49.9%). Most were without health insurance and 99% were poor (<$15,780 annual income). Of this sample, 57.6% (n = 586) described themselves as heterosexual and 42.4% (n = 433) as lesbian. Measurements: Medical Record Audit Form completed by two research assistants with an interrater reliability of more than 95%. Results: There were no significant differences between the lesbian and heterosexual women in family history of breast cancer, current or past alcohol use and history of blackouts or alcohol problems, age at menarche and menopause, use of hormone replacement therapy, ever having had a mammogram or age at most recent mammogram, nor the prevalence of breast cancer. The lesbians reported more breast biopsies and had a higher body mass index; the heterosexuals had higher rates of current smoking, pregnancy, children, miscarriages, abortions, and use of birth control pills. Conclusions: There were significant differences between lesbian and heterosexual women in some of the risk factors for the development of breast cancer. Future studies should sample women of different ages, economic groups, and geographic regions. In particular, the finding that lesbians report more breast biopsies should be further explored.