Evaluation and management of the abnormal gonad.

Diagnostic evaluation of patients with an abnormal gonad is complex because of multifactoral etio-pathogenesis and rarity of the conditions. In the text to follow, we have briefly discussed the embryology and attempted to classify abnormal gonadal disorders. The aims of evaluating such a child are to: (1) establish genetic sex; (2) determine the hormonal milieu; (3) evaluate the anatomy of internal and external genitalia and gonads; and (4) in older children, assess the phenotypic and psychological sex. In newborn children with ambiguous genitalia, the focus is now on accurate gender assignment. A team approach is needed and decisions are based on likely prognosis for behavior and gender orientation. The recent advances in cytogenetics have proven to be helpful in early and accurate diagnosis. In patients with an abnormal gonad, four conditions can present with sexual ambiguity at birth: female pseudohermaphroditism (or "virilized female"), true hermaphroditism, male pseudohermaphroditism (or "undervirilized male") and mixed gonadal dysgenesis. The role of clinical history and examination is emphasized in differential diagnosis and management. Timing of surgery for each of the conditions is discussed.