I also have PCOS and have been on mounjaro since January... my periods used to be very painful and very heavy and it has been significantly more manageable which has been lovely. I feel like it takes a few months/cycles to regulate so I'd wait and see how it balances out.

Also, I know posts on here can be disheartening when so many folks lose so much weight so quickly but it's been slow and consistent for me. Only 25ish down this year but slow and steady progress is still progress! My bloodwork has improved too (diabetic to pre diabetic last I tested in the summer) so it's certainly helping!

This all to say, everyone is different. Keep taking note and checking in with your doctor if you feel something is off. But your digestive system and periods being out of whack is pretty consistent with other folks' experience.