In Switzerland, as in most other countries, the number of adolescents with an active sexual life is on the increase. A statistical analysis of the number of deliveries and of the number of abortions in young women aged less than 19 revealed that out of the total 1413 deliveries in 1978, only 21/1000 involved teenage girls, while the percentage was 45/1000 in 1970. It is obvious that since most teenagers have sexual relations, they either use contraception, or that the number of abortions in that age group, is on the increase. There were, between 1969 and 1978 in the university hospital of Lausanne, 600 requests for abortion among young women aged 12-19, i.e. about 16% of the total requests for abortion; such percentage is about 20-30% in most other countries. Many requests for teenage abortion come from young women residing outside of the Vaud canton, or newly established there. Interviews with patients revealed that girls who had had sex education in schools had sometimes used a contraceptive method. It must be remembered that in Vaud social medical care is very accessible and free to all, and that all schools have been offering well organized sex education programs for 10 years. In the opinion of the author this situation accounts for the low percentage of deliveries and of abortions from Vaud adolescents.