Its strange, but I've always always always been regular. Even at my highest, every 29 days no matter what. The only time I missed was the month my Mom died, and I missed completely, and then it was back as normal the following month. Lol, I always say its because the chicks on my Dad's side of the family are
very fertile, and it has to be because of that.
Of course, I only have 4 a year now, but that's because of Seasonique.