My Aunt Flo is bipolar. This is how she was this year, sorry so long:
We were going on a month long trip in Sept. out of the country, and we were going to start to conceive at that time. Instead, we started earlier, in April. My period didn't come, I thought for sure I was pregnant, then it came a week late and stuck around for a full 3 damn weeks.
In the meantime I had gone into my doctor for my yearly as well as a pre-conception consultation with the NP(my period started the following day). Everything is normal, Aunt Flo makes herself comfy for the next 3 weeks. Then my period stops, I go and do labwork, and it turns out I was not ovulating AT ALL. I have another pre-conception consultation, this time with my OB. By now it had been more than a month again, and this time Aunt Flo was awol, she was not showing up, and I was DEFINITELY not pregnant.
My doctor said, ok we will give her until July 1st to make an appearance, if she doesn't then I go on Provera for 10 days followed by clomid. Provera, btw, is used to start your period as well as stop it. From my understanding doctors use provera (progesterone) specifically for women who are having menstruation problems and are TTC. I have read several forum stories of women using provera to get their periods to stop in order to calculate ovulation.
So go on Provera for 10 days... 11th day Aunt Flo shows up on my doorstep. She only stays for five days. First cycle of clomid at 50 mg. Go do labwork. Progsterone at 10, a strong start the nurse says.
Second round of clomid, this time at 100 mg. AF comes, stays 3 days, leaves. Progesterone this time at 28. Nurse and doc highly encouraged.
Third round of clomid, 100 mg again. AF comes and goes 3 days again. By now we are on our trip and I had no ovulation kit and was not temping. I was relying on cervical mucus, lol.
19dpo I got a faint positive. I'm 12 weeks pregnant now.
I know having those crazy periods are horrible. When my period decides to stay around for so long it literally interferes with my life. If you are actively ttc I would go to the doctor for a pre-conception interview and see what they suggest. Good luck!