I developed migraine in the summer of 2011. It started with horrible vertigo attacks, coupled with other neurological symptoms, so it was confusing at first. I had to undergo a series of tests in the ensuing months, but I was finally diagnosed with vestibular migraine in December 2011.
Receiving a diagnosis was the most helpful thing, because then I was able to educate myself about triggers, treatment, etc. One thing I read is that changes in hormone levels can be a migraine trigger. I can't say for sure how that applies to your experience, because a change in hormone levels may have actually stopped the migraines for you.
The main reason I'm replying to your post is to recommend to you and to anyone else with migraine that you take magnesium supplements. New medical research shows that magnesium supplementation alleviates migraines in at least 50% of migraneurs. After I learned about that, I started taking 250 mg of magnesium, twice a day, and my migraines (which had been recurrent for months) stopped within several weeks! It was like a miracle.
I hope you remain migraine free.