"Pulling out" method

So I just wanted to see how this worked for some women and their partners? And how long you have been doing this and if it's been successful that you haven't gotten pregnant.  I previously used condoms with my boyfriend but recently we havnt and I'm a little worried even though He is very careful and experienced with it. But I'm still counting the days till my period. It would give me some peace of mind if someone would share some of their experience with pulling out as birth control.