Disorders of sex development (DSD) present in different forms but, in most cases, with visible anomalies of the external genitalia. The diagnosis of DSD can have a vast impact on an individual; in addition to concerns about fertility and a higher risk of neoplasia, it may have severe psychosocial impact on the patient. This report presents two apparently healthy cases referred for operation because of unilateral undescended testis. In these two patients, uterine remnants were found during the operation, and underlying DSD conditions were unexpectedly diagnosed. One patient had a 45,X/46,XY mosaic karyotype, while the second patient had persistent müllerian duct syndrome, probably due to an anti-müllerian hormone receptor defect. Both conditions are extremely rare, but the findings reinforce that DSD should be considered in patients with cryptorchidism, especially if other clinical signs are present.