I've never heard of homosexuality being due to "complications during pregnancy", unless you refer to fraternal birth order. I think most theories points to there being a genetic factor, which would also explain why it's so common in the animal kingdom.
Keep in mind that even species birds (who sort of comes from eggs you know) often display homosexual behavior.
Anyway, I wouldn't support of a anti-gay vaccine or anything of the like. Who in the right mind would? I mean, even if you see it as a way for certain individuals to avoid homophobia, just imagine how strange that arguments become when you apply it to racism, for example.
Keep in mind that even species birds (who sort of comes from eggs you know) often display homosexual behavior.
Anyway, I wouldn't support of a anti-gay vaccine or anything of the like. Who in the right mind would? I mean, even if you see it as a way for certain individuals to avoid homophobia, just imagine how strange that arguments become when you apply it to racism, for example.