PIP: The investigation of women in Flanders born between 1931 and 1962 shows that premarital sexual intercourse has become almost general and that the age at the onset of sexual intercourse is steadily declining. Until the 1970s in spite of the improving contraceptive behavior of youngsters, the number of women experiencing premarital pregnancy increased and 1st conceptions occurred at an increasingly younger age. The 1970s marked a turning point: fewer women became pregnant before marriage or in adolescnece. From that time, the contraceptive revolution kept pace with the sexual revolution.