It is possible! I know this because I am almost 14 weeks pregnant now and was using nothing but the "pullout" or withdrawal method of birth control.. Was doing that and even not having sex on and around the days when i thought I would be ovulating. So some defintite misjudgement there on someone's part lol. I used the same method for 4 years without a hitch but it finally caught up to me. So dont make the same error I did!