Research into a common ovarian disorder long known to be a cause of infertility may provide a scientific explanation for why some women are lesbians.
British researchers, working out of a fertility clinic in London, found that nearly 80 per cent of lesbians who came for treatment had polycystic ovaries, compared with 32 per cent of heterosexual women. Polycystic ovarian syndrome, or PCOS, is caused by an imbalance of sex hormones, and one of the main features of the condition is hyperandrogenism -- an abnormally high level of male steroid hormones in women.
"Our results are suggestive of a significantly greater hyperandrogenism in lesbian compared to heterosexual women," said Rina Angrawal, deputy medical director of the London Women's Clinic. She said it is important to understand that the ovarian disorder does not contribute to women becoming lesbians but merely that the syndrome is more prevalent among lesbians.
"We do, however, hypothesize that hyperandrogenism, which is associated with PCOS, may be one of the factors contributing to the sexual orientation of women."
Hyperandrogenism can give women a more masculine appearance, including excess body hair, a deepening voice and loss of breast tissue.
The research, presented yesterday at the annual meeting of the European Society for Human Reproduction and Embryology in Madrid, was done between November of 2001 and January of 2003 and included 254 lesbians and 364 heterosexual women.
About one in five women have polycystic ovaries, which, in addition to fertility problems, can cause irregular menstruation. Women with polycystic ovarian syndrome also seem to be at greater risk for diabetes and heart disease.
Dr. Angrawal said the research team decided to publish results about the syndrome and sexual orientation not to be judgmental but as a means of warning lesbians that they may face additional health risks.