Our results show that progesterone is safe and effective for transgender people. We’re now able to prescribe it, in a trial setting, for those who have been taking oestradiol for at least year. We hope that our findings lead to better hormone treatments for transgender individuals." Koen Dreijerink, endocrinologist at Amsterdam UMC



A note for those in the Netherlands who want it officially (so not really DIY, but whatever…):
Apparently they will prescribe it, but only if you explicitly want it for breast growth. All the other reasons are nor sufficient justification, so if you are trying to convince your endo to give it to you, try that angle! (That’s at least what my GF who has now received it told me about her interactions, I’ll have my call about it on Christmas Eve, so let’s see about it then.)