The withdrawal method, also known as coitus interruptus or the "pull out method", requires great self-control, experience, and trust. With these factors to consider, it is deemed unreliable. It works with the man taking his penis out of the vagina before he ejaculates, limiting the chances of any sperm reaching the ovum. However, because not all sperm are released at climax, pregnancy may still occur.
The man withdraws from inside you before climax to minimize the risk of sperm entering the vagina and therefore reaching the egg. Men who use the withdrawal method must be able to know when they are reaching the point in sexual excitement when ejaculation can no longer be stopped or delayed. If you cannot predict this moment accurately, withdrawal will not be as effective. However, even if a man pulls out in time, pregnancy can still happen. Some experts believe that pre-ejaculation, or pre-cum, can pick up enough sperm left in the urethra from a previous ejaculation to cause pregnancy.