We think of our ears picking up sounds, but don’t consider that inner ear makes sounds too. As the tiny bones of the inner ear move, they give off gives off weak clicking sounds called “otoacoustic emissions.” Listening to inner ear clicks offers scientists a non-invasive way to study of prenatal hormones on the body.

As one of the most delicate mechanisms of the body, the inner ear is highly vulnerable to womb conditions. In general, men don’t hear sounds as well as women, an effect created by prenatal exposure to male hormones that affects the cochlea. Straight women’s cochleas are three times more sensitive than men’s. Maybe that explains all those men who can sleep through the baby fussing in the night?

Lesbian and bisexual women’s inner ears emitted less frequent and weaker sounds than heterosexual women’s. Lesbian’s inner ears are one third as sensitive as straight women’s, meaning their inner ear structures are closer to men’s. The study’s author notes that for lesbians, “Their auditory centers have been masculinized, and the presumption is that so have the sites in the brain that direct sexual preference.” Knowing that lesbians tend to have masculinized inner ears, we can deduce that other parts of their bodies and brains must be affected as well.

This effect was not found in gay men, as we have the same otoacoustic emmisions as straight men.


  • Lesbians: Weaker otoacoustic emissions indicates higher prenatal exposure to male hormones.
  • Gay Men: No differentiation observed.


  • Dennis McFadden, PhD, et al., Proceedings of the National Academy of Sciences, Mar. 1998

This article is part of a series, Written on the Body, exploring the correlations between our body structures and sexual attraction.