Progesterone gay

Prenatal hormones may be seen as the primary determinant of adult sexual orientation, or a co-factor. The hormonal theory of sexuality holds that, just as exposure to certain hormones plays a role in fetal sex differentiation, such exposure also influences the sexual orientation that emerges later in the adult. In a study of 34 people, some adults were more likely to identify as homosexual or bisexual if their mother took progesterone while pregnant.

But is just one of the many factors that might influence our sexuality, say scientists. A new study addresses whether supplementing progesterone during pregnancy, a common practice to prevent miscarriage, could influence a baby’s sexual orientation in later life. Children whose mothers took progesterone while pregnant were more likely to identify as bisexual or gay when they became adults. The results were pretty staggering.

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. Homosexual behavior may have evolved to promote social bonding in humans, according to new research.

The results of a preliminary study provide the first evidence that our need to bond with others increases our openness to engaging in homosexual behavior. Dr Diana Fleischman, of the University of Portsmouth, and colleagues examined the relationship between progesterone and sexual attitudes to explore the role that homosexual behavior may have played in cementing alliances over the course of human evolution.

They found that heterosexual women who have higher levels of progesterone are more likely to be open to the idea of engaging in sexual behavior with other women. Similarly, when heterosexual men are subtly reminded of the importance of having male friends and allies, they report more positive attitudes toward engaging in sexual behavior with other men.

This pattern is particularly dramatic in men who have high levels of progesterone. The hormone progesterone is known to contribute to the formation of social bonds, which have many adaptive benefits for humans. The hormone is produced mainly in the ovaries in women and in the adrenal glands in men. It is one of the main hormones responsible for caring or friendly behavior and levels rise when people have close and friendly interactions.

Women's levels of progesterone peak after ovulation when the chance of becoming pregnant is dramatically reduced. Dr Fleischman said: "From an evolutionary perspective we tend to think of sexual behavior as a means to an end for reproduction. However, because sexual behavior is intimate and pleasurable, it is also used in many species, including non-human primates, to help form and maintain social bonds.

We can all see this in romantic couples who bond by engaging in sexual behavior even when reproduction is not possible. Women were more likely to be motivated to think about homosexual sex when their levels of progesterone were higher. Compared to a control group, men's homoerotic motivation was not increased by priming them with sex but thinking about friendship and bonding caused a measurable change in their attitude to the idea of having sex with other men.

Dr Fleischman, an expert in the influences of hormones on the psychology of women, was studying the effect of progesterone on attitudes towards homosexuality. She questioned whether progesterone, a hormone that has been shown to increase motivation to form close bonds, might also underlie the motivation to affiliate with those of the same sex, sexually.

The researchers first developed a measure of homoerotic motivation through an online survey of participants, with questions including: 'The idea of kissing a person of the same sex is sexually arousing to me' and 'If someone of the same sex made a pass at me I would be disgusted'. The researchers then measured progesterone in 92 women's saliva and found that as progesterone increased so too did openness to the idea of engaging in homosexual activity.

In the next study, the researchers measured levels of progesterone in the saliva of 59 men before all were randomly assigned to one of three groups and asked to complete word completion puzzles, one using friendship words, one using sexual words, and a third using neutral words. In addition, those men with the highest progesterone in the affiliative condition showed 41 per cent greater homoerotic motivation compared to high progesterone men in the other two groups.

Studies of other animals in the great ape family also point to homosexual behavior being used to maintain and forge new friendships. Dr Fleischman said: "Humans are among a group of animals who have sex for many reasons, not just to reproduce. Reasons can include pleasure, a reward, a way of saying 'please be nice to me' or exerting dominance. It's very complex, but it's clear there's a continuum between affection and sexuality and sexuality is fluidity, that is, the ability to engage sexually with those of the same sex or the opposite sex is common.

In humans, much, if not most of same-sex sexual behavior occurs in those who don't identify as homosexual.

progesterone effects on male fetus

The researchers will now explore other contexts and hormonal influences that could increase homoerotic motivation in men and women. They are also interested in seeing how bisexual people might react differently to social cues. Materials provided by University of Portsmouth. Note: Content may be edited for style and length. Science News. Their research is published in the journal Archives of Sexual Behavior.