Dr. med. Dirk Manski

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Monorchidism and Polyorchidism


The state of having only one testicle (monorchidism, also called monorchism) is present in 10–30% of patients with true (nonpalpable) cryptorchidism. A comon cause for a missing testis is intrauterine testicular torsion. Compensatory hypertrophy of the contralateral testis develops; thus, a testicular volume of more than 2 ml indicates monorchism in children with nonpalpable cryptorchidism (Hodhod et al., 2016).


An extra testis results from the accidental division of the gonade during prenatal development, usually before the 8th week of gestation. The supernumerary testis has an epididymis and vas; alternatively, both testes drain together into one epididymis. Polyorchidism is rare.

Index: 1–9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z


Balawender K, Wawrzyniak A, Kobos J, Golberg M, Żytkowski A, Zarzecki M, Walocha J, Bonczar M, Dubrowski A, Mazurek A, Clarke E, Polguj M, Wysiadecki G, Smędra A. Polyorchidism: An Up-to-Date Systematic Review. J Clin Med. 2023 Jan 13;12(2):649.

Hodhod, A.; Capolicchio, J. P.; Jednak, R. & El-Sherbiny, M. Testicular hypertrophy as a predictor for contralateral monorchism: Retrospective review of prospectively recorded data.
J Pediatr Urol 2016, 12, 34.e1-34.e5

Kanbar A, Dabal C, El Khoury J, Halabi R, Assaf S, Mina A, Breidi S, Abdessater M, El Khoury R. Diagnosis and Management of Polyorchidism: A Case Report and Literature Review. Case Rep Urol. 2023 Jun 22;2023:1620276.

  Deutsche Version: Monorchie und Polyorchidismus