Hasn't there also been studies that show a woman can 'decide' if her child is gay or straight? (fetal androgen levels)
The last report on that subject I saw that had any trappings of respectability said that since it's pretty irrefutable that sexual orientation is not genetic, and it's also pretty irrefutable that sexual orientation is not environmental, about the only thing left that could affect it is conditions in utero.
Sexual orientation not genetic? I thought there was some evidence that there are genes that in women cause greater fertility, but in male family members may case homosexuality... I'll google it.
It can influence it but can't outright decide it. Girls with congenital adrenal hyperplasia (where the glands are enlarged and over produce testosterone) have a higher incidence of homosexuality in later life than non affected girls, suggesting the hormones caused their brain to become more like that of a hetero male. http://en.wikipedia.org/wiki/Prenatal_hormones_and_sexual_orientation
