Male pseudohermaphroditism (MPH) is the abnormal development of genitalia in an individual with a 46,XY chromosome complement and testicular tissue. The etiology of MPH is unknown in most cases, which are defined as idiopathic.
Objective: To analyze the data for cases of idiopathic MPH.
Patients and methods: A retrospective study of 29 patients with idiopathic MPH and no uterus.
Results: Four patients had a family history of abnormal sexual development and five had low birth weight. The initial manifestations were sexual ambiguity (26), microphallus and hypospadias (2), and primary amenorrhea (1). Basal and/or stimulated testosterone concentrations showed insufficient testosterone secretion in three patients. Genitography showed a vagina in 13 patients. Male genitoplasties were performed on 21 out of the 24 patients reared as males and female genitoplasties on five patients. Histological studies of the gonads of these showed streak gonads in one, normal gonads in one and signs of testicular dysgenesis in three others. Molecular studies on the SRY gene (17) showed no mutation.
Conclusions: Idiopathic male pseudohermaphroditism is a heterogeneous condition, even within families with a history of this condition. We propose a set of guidelines for the management of these patients.