A study has found that progesterone has an effect on the development of human sexuality. Prenatal exposure to higher levels of progesterone increase the likelihood that individuals will become homosexual or bisexual.
Sexuality is something that people are born with—that's something we know to be certain. However, what's still not certain is the factors that contribute to the determination of human sexuality. New findings suggest that progesterone exposure in the fetal stage may have something to do with it.
Progesterone is a sex hormone present in both males and females, in humans as well as in other animals. It plays an important role in menstruation, pregnancy, and the formation and development of fetuses. It's also a factor in neural development and the production of other sex hormones. Doctors may also prescribe progesterone for pregnant women to deal with complications in pregnancy.
All 34 participants, 17 men and 17 women, in the study had mothers who had received progesterone to prevent miscarriage. All the participants were in their mid-20s and were asked about their sexual orientation, sexual history, and self-identification. They had a carefully structured interview with a psychologist as well.
The researchers also assembled a control group with members who had not experienced prenatal exposure to hormone medication.
The study found that exposure to higher levels of progesterone in the womb made people less likely to identify as heterosexual. 20% of these participants identified their sexuality as something other than homosexual. They were more likely than the control group to have engaged in sexual behavior with the same sex by their mid-20s. The participants were also more likely to be attracted to both sexes than the control group.
Prenatal exposure to progesterone showed a correlation to self-identification as a homosexual, bisexual, or any sexual orientation other than heterosexual. Progesterone may thus have more influence over human sexuality and sexual behavior than we are aware of.
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