My boyfriend and I have been sexually active for over 2 yrs now. We don't use any protection, we just use the withdrawl method. What are the chances I could get pregnant after all this time? Or is he sterile?

You are playing sexual Russian Roulette.

Any time that you have unprotected sex, you increase your chances of getting pregnant. Having unprotected sex for two years increases your chances of pregnancy exponentially.

If you are trying to get pregnant, and you have been unable to, then it could be a medical problem, and both of you shoud see a Doctor to rule out possible causes.

If you aren't trying to get pregnant, and are unprepared to provide for a baby, it might be a good idea to be on some form of birth control before your luck runs out.