I'm not sure if it's "the" cause, possibly one of a series of "tendencies" which can influence variation.
I'll get back to you if I find something .
Check this out.
http://www.freerepublic.com/focus/fr/724179/posts
This site has some good info.
The prenatal hormone thing was one of the most recent “A-ha!, I think we found it” moments, one of numerous attempts. They’ve been desperately trying to prove that gays are “born”, they haven’t found anything yet and never will. If they could have proven the prenatal hormone thing you would have been hearing about it 24/7 for years now.
I had a Ivy League educated shrinker friend who would have been about 90 now if he was alive, he treated and cured homosexuals. Homosexuals who WANTED to change. Obviously, he was educated before this “modern” thinking about gays became vogue. The sad thing is these gays who say “why would I want this”, but refuse to accept that they can be cured because the whole PC crowd is so against this kind of treatment.
Like many of the anecdotes you see on this thread you can always trace a very likely or at least possible cause for homosexuality.