Shantel: Indeed, these studies aren't 100% relevant regarding trans women because they are not about trans women, and not even about "adult", fertile-aged women (I know someone past menopause is still very much an adult, but I can't find the term for "not a child and not an elderly person either").
However, let's face it, there's next to nothing regarding trans people, and realistically speaking, this nothingness is going to last. So we do with what we have, which is much better, you'll admit, than guessing! Not to mention individual experience is sadly not usable to prove anything, and varies a lot. It's hard to go saying progesterone has great effects (or doesn't) when on one side there are people saying it had awesome effects on them, on the other some saying it didn't do anything good, and to the other extreme reports of progesterone-related cancers.
peky: Yeah, what Dr Curtis says makes sense, but like pretty much everything I've seen on the subject, it's still mostly deductions. Not that it makes anything he says invalid, but it's annoying because no one ever has real definite proof on either side. D: Well, you'll say I haven't read much, which is true, but not a lot is accessible to me. I'm not familiar enough with sciences and English to be reading those violently smart-worded texts. (Not to mention research is very low on the list of things I like to do.)
Theo: That was a very nice post. First time I see a true attempt to look at both sides seriously.
Jennygirl: The reason they prescribe pills is that other forms of administration are either expensive/misadapted for trans people (transdermal), controversial/not really proven safe (injections) or not yet approved everywhere (implants). I don't think anyone in their right mind thinks pills are inherently superior. Many however might think that an individual is not at enough risk to justify the massive added cost, which isn't stupid. Not to mention that sublingually taking a pill is better, and I've had no one tell me yet how much better it is. Who knows, maybe it's almost as good as other methods, for a fraction of the price.