Most research on teenage parenthood is concerned with illegitimacy and its determinants such as attitudes toward sex, contraceptive knowledge and practice, family relationships, and cultural factors. Empirical studies on the consequences of illegitimacy are generally limited to problems of recidivism, school dropouts, and welfare dependency. Whether getting married when very young because of pregnancy is more socially advantageous than being an unmarried parent has never been rigorously demonstrated. In initial and follow-up interviews, women who had their first births when they were teenagers were compared to women in their twenties at the time of first birth to examine differences in role aspirations and behavior. Teenage mothers: (1) were less likely to plan the timing of motherhood; (2) found that the onset of childrearing responsibilities had a limiting effect on their role activities; (3) were less likely to realize their work aspirations; and (4) differed from older mothers in that a substantial proportion wanted no more than one child, and a sizeable group wanted four or more children. (Author/HLM)