Orchidopexy is done in cases of undescended testes at the age of:

Spontaneous descent of testes rarely occur after 6 months of age and histologic changes related to infeility occur in the undescended testicle as young as 1 year of age, so surgical repair should ideally be done between 6 months and 1 year. In cryptorchidism the undescended testes may remain in the abdominal cavity, inguinal canal or just outside the external ring. The left testicle is affected more often. In children with bilateral nonpalpable testes hormonal evaluation should be done. If the levels of LH and FSH are elevated and mullerian inhibitory substance is absent the diagnosis of testicular absence can be made . Testicular absence can be confirmed by a negative human chorionic gonadotropin stimulation test. Ref: CURRENT Diagnosis & Treatment: Surgery, 13e chapter 38.