Refraining from any type of sexual intercourse until it is intended for reproduction. This practice is used by primitive societies, primitivist supporters, and some orthodox religions because reproduction is naturally intended as the purpose of sex.
People who oppose mainstream civilization may also choose bioabstinence so they will not contribute to overpopulation, and possibly have the burden of offspring when they are not ready.
Wanna have sex?
No, I practice Bioabstinence. Lets just hug.