Skip to Main Content

Sex development begins in utero but continues into young adulthood with the achievement of sexual maturity and reproductive capability. The major determinants of sex development can be divided into three major components: chromosomal sex, gonadal sex (sex determination), and phenotypic sex (sex differentiation) (Fig. 349-1). Abnormalities at each of these stages can result in disorders of sex development (DSDs) (Table 349-1). A child born with ambiguous genitalia requires urgent assessment, as some causes such as congenital adrenal hyperplasia (CAH), can be associated with life-threatening adrenal crises. Early gender assignment and clear communication with parents about the diagnosis and treatment options are essential. The involvement of an experienced multidisciplinary team is crucial for counseling, medical management, and surgical evaluation/intervention (if needed). Subtler forms of gonadal dysfunction [e.g., Klinefelter's syndrome (KS), Turner's syndrome (TS)] often are diagnosed later in life by internists. Because these conditions are associated with a variety of psychological, reproductive, and metabolic consequences, an open dialogue must be established between the patient and health care providers to ensure continuity and attention to these issues.

Figure 349-1

Sex development can be divided into three major components: chromosomal sex, gonadal sex, and phenotypic sex. T, testosterone; DHT, dihydrotestosterone; MIS, müllerian-inhibiting substance also known as anti-müllerian hormone, AMH.

Table 349-1 Classification of Disorders of Sex Development (DSDs)

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.