46, XY disorder of sex development (DSD; see this term) due to 5-alpha-reductase 2 (SRD5A2) deficiency is a disorder of sex development due to a defect in testosterone (T) metabolism resulting in incomplete intrauterine masculinization. Patients present an ambiguous external genitalia which varies from a female with a blind vaginal pouch to a fully male phenotype with pseudovaginal posterior hypospadias (see this term) or only micropenis.