An estimated 40% of US females now 14 years of age can be expected to experience pregnancy by age 19 years, and the majority of these pregnancies will be unintended. In 1981, there were 1,343,200 pregnancies among US females under 20 years of age and 448,570 abortions in this same age group. The abortion ratio is highest for adolescents under 15 years of age (1379 abortions/1000 live births), while the abortion rate is highest for 18-19 year olds (61.8/1000). When compared to adult women, adolescents obtain abortions at a later gestational age--a factor that increases both the psychological and medical risks of the procedure. Adolescents are also more likely than adults to base their decision regarding the pregnancy on the opinions of significant others. Comparative studies have shown teenagers who continue a pregnancy to have underdeveloped conceptualizations of the future, high levels of anxiety, and an external locus of control. Adolescents at greatest risk of psychological sequelae of abortion are those with pre-existing mental illness, strong religious beliefs, limited coping skills, a narrow support network, and abortion at later gestational stages. If the teenager feels pressured by her family to terminate the pregnancy, she is also at high risk for adverse psychological sequelae and a repeat pregnancy soon after abortion. Thus, counselors should maintain a neutral position while helping teens to examine the positive and negative aspects of their options. In terms of medical effects, teenagers have been shown to have the lowest risk of all age groups for abortion-related mortality. However, because of the later gestational age at which adolescents seek abortion, there is a higher risk of complications such as endometritis. Emphasis should be placed on expediting the abortion decision making process among adolescents to reduce delays and the potential risks.