Risk factors for reproductive and breast cancers among older lesbians

To determine if older lesbians have more breast and gynecological cancer risk factors compared with their heterosexual sisters.

Using multiple methods, including respondent-driven sampling with the lesbian as the index participant, a sample of 370 lesbian-heterosexual sister pairs aged >or=40 completed an anonymous survey about their health. For this secondary data analysis, we extracted data on an older subset of this group, those sister pairs with at least one sister >50 years (n = 42 pairs or 84 women). For this project, we explored the breast and gynecological risk factors for cancer in these women. Comparisons between the sisters were generated using paired t tests, analysis of variance (ANCOVA), and McNemar's chi-square.

Compared with their sisters, lesbians had significantly more education (p < 0.001), fewer pregnancies (p < 0.001), less total months pregnant (p < 0.001), fewer children (p < 0.001), and fewer total months breastfeeding (p < 0.001). Lesbians in this sample tended to have higher body mass indices (BMI) (p = 0.08) and to exercise fewer times per week (p = 0.07). Differences in smoking and alcohol use were not statistically significantly different. The lesbians performed breast self-examinations significantly less than their sisters (p < 0.05).

These findings suggest that older lesbians may have greater risk factors for some, not all, reproductive cancers when compared with their heterosexual sisters, specifically, increased risk for breast, ovarian, and endometrial cancer but decreased risk for cervical cancer. Further research should be done to determine if these risks translate into actual disease for lesbians as well as culturally appropriate ways to modify the risks among lesbians.