In dem Buch „Brain Sex“, welches ich bereits hier zitiert und hier empfohlen habe, hat eine interessante Passage zu pränatalen Stress und Homosexualität:
So what is the original, biological cause of sexual deviation? If it’s the hormones which so afffect the sexuality of the child and adult, what happens to upset those hormones in the first place?
The first clues came from those rats again. It is known that high stress levels in mothers lower the level of male hormone in the womb. Experiments showed that when pregnant rats were subjected to severe stress, the resulting male offspring were attracted to other male rats – indeed that the rats were homosexual, apparently as a consequence of the stress endured by their mothers. Dorner was intrigued by the news. Understandably, he could not put a laboratory-full of pregnant women undersevere stress, but he could examine the results in the laboratory of history.
He looked at the years of the Second World War – a time when the inhabitants of his country could be said to have been living under more than usually trying circumstances. Dorner found that out of about 800 homosexual males, significantly more were born during the stressful war and early post-war period than in the years before and some time after the war. The highest number corresponded with the last months of the conflict. Two-thirds of the homosexual men and their mothers reported experience of severe, or moderate, maternal stress during their pre-natal life – with factors such as bereavement, bombings, rape, or severe anxiety. On the other hand, none of the mothers of heterosexual men in a control sample had been the victims of severe stress, and only 10 per cent of moderate stress, during pregnancy.
Low pre-natal, male hormone levels can be affected by factors less drastic than major global conflict. Taking inappropriate medication is one of these. Barbiturates, one of the most widely prescribed and abused classes of drugs, are thought to have been prescribed in as many as 25 per cent of pregnancies between the 1950s and the 1980s. In animal experiments involving exposure to barbiturates the drug acted directly on the neural tissue, and indirectly through the brain-sexing substances secreted by the foetus.
Among the observed results was an ‚alteration of behavioural and physiological sex differences‘. In humans the predicted results would include ‚psychosocial maladjustment, and demasculinisation of gender identity and sex role behaviour in males‘. The implication – and it is true of many drugs – is that pregnant women would be well advised to avoid barbiturates; it is comforting to know that they.
Das sind aus meiner Sicht interessante Bestätigungen der Theorien. Es zeigt sich auch wieder einmal, dass der Hinweis, dass Menschenexperimente nicht erlaubt sind und deswegen die Theorien nie letztendlich getestet werden können, falsch ist: Es findet sich immer wieder eine Sonderkonstellation oder eine unterschätzte Nebenwirkung eines Medikamentes, die zur Überprüfung dienen kann.
Noch ein paar weitere Studien zu dem Thema:
Die Dörner Studie:
Out of 865 homosexual males who were registered by venerologists in 6 districts of the GDR highly significantly more homosexuals were born during the stressful war and early postwar period of the Second World War, i.e. between 1941 and 1947 (with a maximum of relative frequency in 1944-1945), than in the years before or after this critical period. This finding suggests that stressful prenatal (or perinatal) events may represent an aetiogenetic factor for homosexuality in human males.
Quelle: Prenatal stress as possible aetiogenetic factor of homosexuality in human males.
oder diese:
Background: Studies of rats have shown that mothers who are subjected to stress during pregnancy are more likely than mothers who are not stressed during pregnancy to have male offspring who exhibit female-typical sexual receptivity postures (lordosis) in the presence of other males following the onset of puberty. More recent animal experiments have indicated that prenatal exposure to alcohol affects the sexual preferences of male offspring in ways that are similar to the effects of prenatalstress. Research with human subjects have thus far yielded inconsistent findings regarding the effects of prenatalstress on male sexual orientation, and no research has yet addressed the possible involvement of prenatal exposure to alcohol or other widely used recreational drugs, such as nicotine. Purpose: The present study was undertaken to determine if prenatalstress could be one of the causes of variations in sexual orientation in humans, both singularly and in conjunction with prenatal exposure to alcohol and nicotine. Methods: Over 7500 offspring and their mothers provided information regarding the offspring’s sexual orientation and the mother’s stressful experiences and use of alcohol and nicotine during pregnancy. Results: Findings indicate that prenatalstress has a modest but significant effect on the sexual orientation of male offspring, particularly when the stress occurred during the first trimester of pregnancy. Regarding prenatal exposure to alcohol, no evidence was found to suggest that it impacted offspring sexual orientation of either males or females. Prenatal nicotine exposure, however, appears to significantly increase the probability of lesbianism among female offspring, especially if the exposure occurred in the first trimester along with prenatalstress in the second trimester. Conclusion: The present study is consistent with animal models suggesting that prenatalstress disrupts the typical sex hormonal milieu within which male fetal brains are sexed, thereby feminizing/demasculinizing the male’s sexual orientation. However, little support was found for similar effects of prenatal alcohol exposure. In the case of prenatal nicotine, this study is the first to suggest that this drug has masculinizing/defeminizing effects on the sexual orientation of female offspring.
Alles Evolution 