Kelley_aus intoned
QuoteCan you say with any certainty that the growth wouldn't have happened without progesterone? The trans community id full of anecdotes like this - even without any real proof.
Have I run a double blind trial? Obviously not. I started and continue progesterone principally for effect on libido. I talked extensively with my psychiatrist about it. My feeling was that hormonal - brain effects are different between individuals similar as with antidepressants. You're working with an amazingly complex system. The effect on libido was pronounced, after 9 months of nearly zero interest in sex I had erotic feelings again. I also find if I take progesterone for more than a couple of weeks I run into some depression.
Increased boob size is a minor bonus. Can I be certain observed change in shape was due to progesterone? Of course not. Am I certain that after 9 months of steady growth of my breasts with a conical ahape, an additional 2 months of estrogen plus progesterone changed the shape? Yes I am.
I'm sorry, your tone feels verging on pejorative. What is the difference between "real" proof you ask about and simply proof? I'm a scientist and engineer, I know the value of controlled studies and I also know the things that are really hard to determine that way.
Case in point, the APA working group on transgender diagnosis for the latest version of the DSM observed that WPATH is based on effectively no high quality studies however they also conclude that WPATH works. So we have very different views coming from the two bodies in the medical establishment that have the greatest influence in our lives.
Poincaré wrote, I believe it was in "Science and Hypothesis" that whatever the apparatus used in taking observations, ultimately it's the act of observing that results in the measure. His point was to establish that whether using a handspan or the most precise equipment available to technology, the act if determination happens in the mind.
We've come a long way since Poincaré, and yet we are still human.
Before I worked as an engineer and then scientist, I worked as a machinist, before that as a blackmith. Today I try to eek out as much of my livelihood as I can in blowing glass (using tools I fashioned in our blacksmithing shop on the other side of the infinite corridor). Shape, form and measure have been my life for the last 40+ years. Again, I'm pretty darned sure the shape of my boobs changed and that the stimulus for that change was the progesterone.