1) please don't say tranny, that's basically our N word. Please don't call your daughter that, either lol.
2) I think that you're trying to give a biological justification for an increase that isn't fully biological. The number of transgender people didn't change, the number of transgender people who are comfortable living as transgender is what changed... There could be some pronounced effect that these two could have on sex -- I'm not saying it's impossible, however the root cause is most definitely social setting. (And this has been proven.) The way you are looking at this is that transgender people suddenly appeared -- but if you look at the statistics, there is a striking correlation with the number of transgender people in a country and advocacy rate for transgender rights. Though your hormone cycles could certainly have an effect on a child, generally in menopause this is in the form of less estrogen -- not more. It is common for geriatric pregnancies to lead to more androgens in pregnancy. But biology, especially endocrinological subsets of biology, becomes very complicated -- and this is not my domain I'm more of an applied scientist who looks at Social data.
3) Transgender people, and intersex people, are not a birth defect. We have existed at relatively the same population size for all of recorded history. The only exception in history is now.

I want to stress that I don't think it's impossible that some of these things could have effects, however the primary catalyst for more transgender people being noted in censuses is definitely just society becoming more accepting of transgender people.