Let me first say that I really dont know much about the subject, other than my own experiences... i am 23 and have been riding for four years.


This happened to me when i first got my bike--- only for 2 periods i believe. I am sure it's because of the body fat that dropped off. However, it went back to normal

--until i had my bike wreck which caused my body to go into shock (and unable to do physical activity for 8 months). Then i lost it again for 2 months. I was convinced i was the virgin mary and somehow got pregnant without my knowing ha!!!

however, NOW that I am training everyday--it's like my body decided to go turbo on me. 7 days straight of womanhood...wahh

So yea, i second the checkup with the OBGYN. At least give their nurse line a call--they should call you back by the end of the day and give you some kind of info. Hope this helps!! Good luck