Contraception in adolescence presents some particular psychological and sexual aspects. From the experience of 2 family planning centers in Lausanne, Switzerland, it is concluded that most of the patients attending the centers began their sexual life at the age of 16-17; most of them used contraceptive methods that were very unreliable, in spite of a sex education program that is well organized in the canton of Vaud; 88% of them had already had sexual relations before attending the center s; the number of adolescents visiting the centers is increasing each year. There is, however, still resistance to contraception, for conscious or unconscious motives. The most frequent causes of resistance are analyzed and generally attributed to immaturity. Physicians should be aware of the psychological conditions of each case and provide the appropriate advice and assistance.