The Collaborative International Dictionary of English v.0.48:

contraception \contraception\ n.
   the intentional prevention of conception or impregnation,
   especially when accomplished by the use of contraceptive
   medications or devices; a form of birth control.
   [WordNet 1.5]

WordNet (r) 3.0 (2006):

contraception
    n 1: birth control by the use of devices (diaphragm or
         intrauterine device or condom) or drugs or surgery [syn:
         contraception, contraceptive method]

Moby Thesaurus II by Grady Ward, 1.0:

19 Moby Thesaurus words for "contraception":
   aridity, barrenness, birth control, dearth, dry womb, dryness,
   family planning, famine, impotence, ineffectualness, infecundity,
   infertility, planned parenthood, sterileness, sterility,
   unfertileness, unfruitfulness, unproductiveness, withered loins