Disorders of sex development: neonatal diagnosis and management.

The disorders of sex development (DSD) refer to the insufficient virilization of the external genitalia of a 46,XY fetus or the excessive virilization of those of the 46,XX fetus. Some of these disorders are associated with karyotype abnormalities. DSD arise from abnormal gonadal determination or sex differentiation, as in the case of the abnormal testosterone synthesis or androgen insensitivity of 46,XY DSD. The impact of environmental endocrine disrupting chemicals during fetal life requires further investigation. The basic investigations should include SRY gene sequencing and measurement of 17-hydroxyprogesterone, anti-Mullerian hormone, and testosterone. Choosing the sex of rearing is difficult and the decision must be made by an experienced multidisciplinary team.