Indolamine derivatives as anti-fertility agents

A method of inducing aspermatogenesis in male mammals requiring anti-fertility treatment which comprises administering to the mammal an anti-fertility therapeutically effective amount of

• (a) a compound of the formula:
• ##STR17## where m is an integer from 1 to 4
• X represents hydrogen or --OH
• R represents Ar, ##STR18## Ar represents ##STR19## R.sub.1 represents hydrogen, fluoro, chloro, lower alkyl or lower alkoxy, R.sub.2 and R.sub.3 each, independently, represent lower alkyl, or
• R.sub.2 and R.sub.3 together with N represent ##STR20## wherein n is 1, 2 or 3,
• R.sub.4 represents hydrogen or lower alkyl, and
• R.sub.5 represents hydrogen or lower alkyl, unsubstituted phenyl or phenyl mono- or di-substituted with fluoro, chloro, lower alkyl or lower alkoxy, or
• (b) a compound of the formula:
• ##STR21## where R' is Ar or ##STR22## Ar, R.sub.1, R.sub.2, R.sub.3, R.sub.4 and R.sub.5 are as defined above, or a pharmaceutically acceptable acid addition salt thereof.