OP here -- thanks! I too have an ovarian cyst, or did a month/6 weeks ago when I had some day 3 bloodwork done. Not on any fertility meds curently but good to know that bugger might be screwing things up.

hard to say. going through this myself right now with several 21-day cycles. had an ovarian cyst that resolved itself, and thinking that might be the cause. Apparently clomid slows down your cycle, so if you move on to that it might make a difference. Of course there are side effects and risks too (including ovarian cysts, so that's a vicious little cycle...)

OP, the same thing happened to me
I am very regular and I had a 19 day cycle for no apparent reason

I talked to my doctor and he said that it can happen but didn't have an explanation except he assured me that it was not early menopause- so you can take comfort in that

Have been trying for 3 years. For the first time, I had a 20 day cycle (usually 28-ish). Now the current cycle looks like it might be weird too, as I am on day 10 and OPKs are not getting darker like usual. Ugh wtf? I am 34 so hoping it's not early menopause or something.