Contraceptive method

摘要

Contraceptive method comprises maintaining in the genital tract of a female mammal a pyrazolone derivative in a concentration effective to inhibit the fertilization of ova. In addition to effectively inhibiting the enzymes or other sperm components necessary for conception, the compounds used in the method of the invention are advantageous in having low toxic, caustic or irritating properties, so that the contraceptive compositions are suitable for long-term use without adverse side-effects.