Last night my girlfriend and I had drunk sex, she has been on her period for about 4 days or so, I know for a fact that I busted in her.. And I need to know if it's possible and how likely it is she could get pregnant? I'm hearing mixed things on this issue.

She most certainly can. And many women DO get pregnant this way. Are you ready to be a dad yet?

If she happens to ovulate on the early side, or has an off ovulation, pregnancy could be possible. Remember that sperm can survive in the few days leading up to ovulation. It's not usually the most likely time to become pregnant, but it's not impossible.

Since it just occurred last night, it would be wise for her to obtain an emergency contraceptive, such as plan B, from a pharmacy today as a precaution. She does not need a prescription.