The risks and consequences of adolescent fertility are discussed. Childbirth before the age of 20 is more dangerous to the mother and infant than it is for older women. A growing proportion of all births is attributable to women under 20, menarche appears to be occurring earlier, but the age at marriage is increasing. The effect of urbanization on traditional customs and the lack of family planning services have contributed to the increase in early births. Pregnancy during adolescence poses an increased risk if maternal and infant morbidity and mortality results in an increase in cumulative fertility, and restricts the opportunity for socioeconomic advancement. Legal and social restraints often hinder an unmarried adolescent in obtaining family planning services. The attitude in developed countries, however, is changing to allow adolescents greater access to contraception and abortion services. Contraceptive methods that may be used by adolescents include periodic abstinence, coitus interruptus, oral contraceptives, vaginal diaphragms, condoms, IUDs, and postcoital methods. Recently, more and more abortions are being performed on adolescent women in most countries. Obstacles to and recommendations for sex education for adolescents are reviewed, and sources for sex education materials are listed.