WordNet (r) 3.0 (2006):

family planning
    n 1: limiting the number of children born [syn: birth control,
         birth prevention, family planning]

Moby Thesaurus II by Grady Ward, 1.0:

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