My girlfriend and i had sex yesterday unprotected however i pulled out well before i finished. she was on her period. should she take plan b.

Things to ponder: Pregnancy has been documented from exposure on ANY DAY of a woman's cycle including during menses. It only tales one sperm, which are constantly leaking during sex and an egg ready to enter the Fallopian tubes. Menses usually but does not always reflect timing or status of ovulation. Those with irregular cycles are most at risk. The pull out method is like Russian roulette.