Pregnancy Possibility

I started my period when I was about 12, but instead of having a month-to-month cycle, I had a period around ever two to three months. I was nevet able to track it. I am very healthy, but I am a very active athlete. I have always been curious about whether or not my cycle has anything to do with my chances of getting pregnant one day with my spouse. I have been on the pill since July 2012 and I haven't had a period since. Anyone know??