<unk> , also known as withdrawal, pulling out, or the pull-out method, is a method of birth control in which a man, during sexual intercourse, withdraws his penis from a woman's vagina prior to ejaculation and then directs his ejaculate (semen) away from the vagina in an effort to avoid insemination. :Population Action International (1991). "A Guide to Methods of Birth Control." Briefing Paper No. 25, Washington, D. C. This method was used by an estimated 38 million couples worldwide in 1991.<unk>  does not protect against sexually transmitted infections (STIs/STDs).
Coitus interruptus
Echinostoma
Gonyaulax
Necator americanus
Craniopagus parasiticus
Ephedra distachya
Schistosoma intercalatum
Mitragyna speciosa