[The reproductive characteristics of adolescents and young adults in Mexico City].

This article presents the preliminary findings of the Survey on Teenagers and Youth Reproductive Behavior in the Metropolitan Area of Mexico City, which contains information on 1,010 teenagers and young adults from 10 to 25 years of age interviewed in 1987. The average age was 17 years; 51.7 per cent of those interviewed were male and 48.3 per cent were female. A total of 14.6 per cent were married, being the average age at marriage 19.2 years for males and 17.8 years for females. Menarche occurred at an average age of 12.4 years, and spermarche at 14. Of those interviewed, 32.7 per cent have had sexual intercourse at least once in their lives. The average age at which sexual activity had begun, in the case of males, was 16 years and for females, 17 years. Of this group, 33.8 per cent stated that they had used some form of contraception during the first sexual intercourse; the contraceptive methods used most often were rhythm and withdrawal. The main source of supply of other methods is the pharmacy, in 67 per cent. 18.4 per cent of women had been pregnant, and 20.4 per cent of men's partners had presented this same condition. The first pregnancy occurred at 17.8 years for women and 18.7 for men. Of those men and women with a pregnancy experience 66.1 per cent and 57.3 per cent, respectively, stated that their first pregnancy was an unplanned one. Also, first pregnancy was related to their first marriage in 48.1 per cent of women and 82.4 per cent of male. The data presented here will reinforce current knowledge and will enable us to obtain a profile of the reproductive behavior of teenagers and young adults in the metropolitan area of Mexico City.