Contraceptive
/ˈkɒn.tɹəˌsɛp.tɪv/
noun
A mechanism or means by which conception as a result of sexual intercourse can be prevented or made less likely.
“Putting a pig's bladder over one's penis during intercourse is not a good contraceptive.”
adjective
That acts to prevent conception as a result of sexual intercourse.
“She was careful to take her contraceptive pill at the same time every day.”