Progesterone and bisexuality: Is there a link?
Giving progesterone to prevent miscarriage can influence a baby's sexual orientation. Bisexuality is quite common among men and women whose mothers received added doses of progesterone to prevent miscarriage.
Both men and women naturally produce progesterone. The hormone is produced in the ovaries, the placenta (when a woman gets pregnant) and the adrenal glands. It helps prepare your body for conception and pregnancy and regulates the monthly menstrual cycle. It also plays a role in sexual desire.
Physicians often prescribe progesterone to support fertilization, prevent miscarriages or premature births, and to increase babies' birth weights.
The study was led by June Reinisch, Director Emerita of The Kinsey Institute and is published in the journal Archives of Sexual Behavior. The research is based on 34 mothers in Denmark given progesterone to prevent miscarriage. The 34 participants were drawn from the Copenhagen Perinatal Cohort, which is made up of information collected from virtually all children born between 1959 and 1961 at the university hospital in Copenhagen, Denmark.
The 17 men and 17 women selected for the study were chosen because their mothers exclusively received progesterone lutocyclin to prevent a miscarriage. These men and women were compared with a carefully selected control group who were not exposed prenatally to lutocyclin or any other hormone medication. At the same time, the control group matched the study participants based on 14 physical, medical, and socioeconomic factors. All participants were in their mid-20s when asked about their sexual orientation, self-identification, attraction to each sex, and sexual history using — questionnaires and a structured interview with a psychologist.
Men and women whose mothers were treated with progesterone, were significantly less likely to describe themselves as heterosexual. In fact, one in five (or 20.6 percent) of progesterone - exposed participants do not identify as heterosexual.
Compared to the untreated group, the chances were greater that by their mid-20s they had already engaged in some form of same-sex sexual behavior (in up to 24.2 percent of cases), and that they were attracted to the same (29.4 percent) or to both sexes (17.6 percent). Both exposed males and females also had higher scores related to attraction to men.
The research team believes more studies on offspring of women medically treated with progesterone and progestogens during pregnancy, as well as studies examining the effects of natural variation in prenatal progesterone levels, are needed to provide more insight into the role that this hormone plays in the development of human behavior.
Prenatal sex hormone levels affect physical and behavioral sexual differentiation in animals and humans. Although prenatal hormones are theorized to influence sexual orientation in humans, evidence is sparse. Sexual orientation variables for 34 prenatally progesterone-exposed subjects (17 males and 17 females) were compared to matched controls (M age = 23.2 years). A case–control double-blind design was used drawing on existing data from the US/Denmark Prenatal Development Project. Index cases were exposed to lutocyclin (bioidentical progesterone = C21H30O2; MW: 314.46) and no other hormonal preparation. Controls were matched on 14 physical, medical, and socioeconomic variables. A structured interview conducted by a psychologist and self-administered questionnaires were used to collect data on sexual orientation, self-identification, attraction to the same and other sex, and history of sexual behavior with each sex. Compared to the unexposed, fewer exposed males and females identified as heterosexual and more of them reported histories of same-sex sexual behavior, attraction to the same or both sexes, and scored higher on attraction to males. Measures of heterosexual behavior and scores on attraction to females did not differ significantly by exposure. We conclude that, regardless of sex, exposure appeared to be associated with higher rates of bisexuality. Prenatal progesterone may be an underappreciated epigenetic factor in human sexual and psychosexual development and, in light of the current prevalence of progesterone treatment during pregnancy for a variety of pregnancy complications, warrants further investigation. These data on the effects of prenatal exposure to exogenous progesterone also suggest a potential role for natural early perturbations in progesterone levels in the development of sexual orientation.
Sexual orientation Prenatal progesterone exposure Bisexuality Sexual behavior
Reference: Reinisch, J.M. et al. (2017). Prenatal Exposure to Progesterone Affects Sexual Orientation in Humans, Archives of Sexual Behavior, DOI: 10.1007/s10508-016-0923-z
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Apr 12, 2017 Fetal Timeline Maternal Timeline News News Archive
"Progesterone exposure was found to increase non-heterosexual self-identification,
attraction to the same or both sexes, and same-sex sexual behavior."
June Reinisch PhD, Director Emerita of The Kinsey Institute, USA
Image credit: LGBT — or lesbian, gay, bisexual, and transgender pride.