Coitus interruptus (withdrawal or the pull-out method), is a birth-control technique widely used for thousands of years as a method of contraception. This method was used by an estimated thirty-eight million couples worldwide.
In withdrawal method, the man pulls his penis out of his partner's vagina before ejaculation. For the success of this method, man must need self-control and must know when he is about to ejaculate.
A well experienced man can pull out his penis 2-3 seconds before ejaculation and rub it against the groin (junction of the torso with the legs) area or the navel (belly button) area of the female, until ejaculate. It is important that none of the semen touches or enters the vagina.
Withdrawal method is less problematic for married and long-term monogamous couples and a recent study conducted by Guttmacher Institute show that withdrawal method is almost as effective as condoms use in preventing pregnancy.
Man's pre-ejaculate fluid contains no sperms by itself, but there may be left over semen present in a man's urethra from a previous ejaculation. Urination of men after ejaculation and before next vaginal penetration is helpful to wash away sperms in the urethra and researches shows that, urine significantly decreases sperm motility due to the changes in pH and osmolarity. It is important that, man must wash his penis with soap and water before sex for a better sucess rate of this method.
Yes, it is a birth control method with 4% perfect use failure rate. This means four women in 100 would get pregnant in one year. That's similar to the effectiveness of the female condom. This 4% failure rate is due to the lack of expertness in this method.