Pubertal development of the first cohort of young adults conceived by in vitro fertilization in the United States.

To characterize pubertal development of the first generation of young adults born as a result of in vitro fertilization (IVF). Demographic, clinical, and body size characteristics were examined regarding developmental milestones. Cross-sectional. Academic center. Young adults (18-26 years) conceived by IVF (no gamete/embryo manipulation) 1981-1990. Self-administered questionnaire. Age at puberty onset, body size. Of 560 eligible young adults, 173 completed the survey (response rate 30.9%). We analyzed data on 166 respondents (71 male and 95 female). No cases of delayed or precocious puberty were observed in the study sample. As expected, age at puberty onset was significantly higher among male subjects (12.3 years) compared with female subjects (11.5 years). A few developmental milestones were predicted by maternal age and infertility diagnoses. For both genders, a direct association was noted between age at puberty onset and height achieved in young adulthood. Structural equation models suggested an inverse relationship of female gender with age at puberty onset and body mass index. In vitro fertilization-conceived young adults did not exhibit pubertal abnormalities. Female gender and age at puberty onset independently predicted body mass index of IVF offspring in young adulthood.