RT Book, Section A1 Fitzgerald, Paul A. A2 Papadakis, Maxine A. A2 McPhee, Stephen J. A2 Rabow, Michael W. A2 McQuaid, Kenneth R. SR Print(0) ID 1193161051 T1 Cryptorchism T2 Current Medical Diagnosis & Treatment 2023 YR 2023 FD 2023 PB McGraw-Hill Education PP New York, NY SN 9781264687343 LK accessmedicine.mhmedical.com/content.aspx?aid=1193161051 RD 2024/04/24 AB One or both testes may be absent from the scrotum at birth in about 20% of premature or low-birth-weight male infants and in 3–6% of full-term infants. Cryptorchidism is found in 1–2% of males after 1 year of age but must be distinguished from retractile testes, which require no treatment. Infertility or subfertility occurs in up to 75% of men with bilateral cryptorchism and in 50% of men with unilateral cryptorchism. Some patients have underlying hypogonadism, including hypogonadotropic hypogonadism.