This study was carried out in Yaounde (Cameroon) in 1995 to determine the knowledge, attitude and behaviour of teenage mothers towards family planning. The study was based on a questionnaire administered at household level drawn from previously determined clusters. It was accomplished by recruiting 462 teenage mothers with ages ranging from 14 to 19 years and who had 1 to 3 children. On the whole, 93.9% had heard of family planning, 72.5% had heard of family planning centres, but only 43% had been to one of these centres at least once. With regards to contraceptive prevalence, 62.1% affirmed the use of a contraceptive method at the time of the study with periodic abstinence being the most widely used (35.9%). Besides the common methods, some teenage mothers made use of herbal concoctions and vaginal douching, sometimes with permanganate or the taking of tablets. Nineteen per cent of respondents had had between one and four episodes of induced abortion. According to these teenagers, the ideal average age for first delivery is 19.7 +/- 2.5 years, whereas that of nubility is 22.8 +/- 3.3 years, a difference of 3 years. This suggests that on the whole, teenage mothers believe that first delivery must precede marriage.