First of all WELCOME to the forum!
I had normal periods until i was about 18 or so that they began to get irregular. Didn't pay too much attention to it. i did go to the doctor and she suggested i take bcp's to regulate it, but since i was a teen and didn't care too much, just very happy that i wasn't getting my period, lololol.
long story short, i have pcos. After DH and i decided that we'd like to start our family we went to the doctor to get more info because i wasn't menstruating nor getting pregnant. Did all the testing, my FSH & LH were low as well. Then referred to RE. They put me on Metformin (1500mg) then tried clomid, then about 3 or 4 cycles of IUI's but with those either i wouldn't respond well or i'd respond too much. they couldn't control it very well. So we moved on to IVF, first cycle got pregnant, however, i m/c at 12wks.
i recommend you do a lot of research on pcos, since its very hard to determine the symptoms, but something to keep in mind.
hope this was helpful
