Growth hormone deficiency causing micropenis: Lessons learned from a well-adjusted adult

This report of a 46, XY patient born with a micropenis consistent with etiology from isolated congenital growth hormone deficiency is used to (1) raise the question regarding what degree testicular testosterone exposure to the central nervous system during fetal life and early infancy has on the development of male gender identity, regardless of gender of rearing; (2) suggest the obligatory nature of timely full disclosure of medical history; (3) emphasize that virtually all 46, XY infants with functional testes and a micropenis should be initially boys except some with partial androgen insensitivity syndrome; and (4) highlight the sustaining value of a positive long-term relationship with a trusted physician (R.M.B.). When this infant presented, it was commonly considered inappropriate to gender assign an infant male whose penis was so small that an adult size was expected to be inadequate, even if the karyotype was 46, XY, and testes were functional. Concomitantly, female gender assignment was considered the appropriate decision, believing that parental rearing in the assigned gender was considered the major factor determining established adult gender identity. Full disclosure of medical information was considered inappropriate. Progress in appreciating the complexities of gender identity development, which is not yet completely understood, and sexuality, coping ability, and outcome data has resulted in a change of practice in initial gender assignment. A 46, XY individual with functional testes and verified androgen responsiveness should be assigned and reared as male, regardless of penis size. Without androgen responsiveness, the multiple factors must be carefully considered and disclosed.