My periods have always been regular (between 26 and 29 days every month). My husband and I started trying for a baby in July 2008. After 6 months of trying, because I am 33, my doctor ran some tests (all normal), and prescribed Clomid. First round was 50 mg, and my period was a couple days late. Next round was 100 mg, and again, my period was only a couple days late. My doctor said this was normal. Third round was 100 mg again, and my period was way late. After a week, and two negative home tests, my doctor did a blood test, and it was negative. Another week, same thing, all negatives.
She prescribed prometrium to either strengthen my uterine lining for the embryo to implant, or to get a period. I got my period today, three and a half weeks late from the expected "Clomid date" (two days later than my normal). My question is why would my period be SO late when using Clomid, since Clomid is supposed to control ovulation, which controls when my period starts? And I had symptoms of ovulation, so I'm sure that I did this month.

I'll be asking my doctor the same question, but the office isn't open for three more days, and the curiosity is killing me. Thanks!

I'm wondering why your doctor put you on anything if your tests all came back normal? Was it determined that you weren't ovulating? Did your husband have testing done as well?

Some women will experience changes in their cycles when using Clomid. As you said, it's to stimulate ovulation... but that does not guarantee a period.

Was your doctor monitoring you each cycle you were on the Clomid? Has your progesterone level been checked as well?
Usually that will be at a good level if the Clomid is at a good level... prometrium can help with that.