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Germ cell loss can be observed early in congenital cryptorchid testes, and the longer the testes remain undescended the more the testicular structure deteriorates. Therefore, orchiopexy at the age of 6 to 12 months is recommended to sustain as good spermatogenesis as possible.
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Orchiopexy corrects the inappropriate temperature of the testis, but it may not reverse the damage that underlies cryptorchidism in the first place.
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History of surgery for bilateral cryptorchidism has been associated with
Endocrinology and Metabolism Clinics of North America
Cryptorchidism and Fertility
Section snippets
Key points
Germ cell proliferation during childhood
Quantitative data on germ cell populations in fetal and childhood testes have been analyzed in rather few studies.1, 2, 3, 4 After migration of primordial germ cells to gonadal ridges, testicular cords are forming at 8 weeks of gestation, and germ cells inside the cords are called gonocytes. They normally move from the central part of the testicular cords to the basement membrane and form the spermatogonial layer by the age of 3 months. At that time, Adark and Apale spermatogonia start to
Germ cell loss in cryptorchidism
In cryptorchid testis, germ cell development is not normal, and even in the contralateral descended testis, abnormalities are common.6 The number of germ cells declines faster during the first 3 years after birth in the undescended testes than in the contralateral or normal testis.7, 8 This decline is also reflected by testicular size that lags behind in the undescended testis as compared with the normal one.9, 10 Timing of the treatment is an important determinant of testicular growth.
Effect of treatment on germ cells—human chorionic gonadotropin, gonadotropin-releasing hormone
Treatment with either human chorionic gonadotropin (hCG) or gonadotropin-releasing hormone (GnRH) stimulates testicular growth and initiation of spermatogenesis both in the cryptorchid and descended testes. Part of the growth after hCG treatment is related to inflammatory reaction where vascular permeability in the testis increases and both erythrocytes and leukocytes leak into the interstitial tissue.16, 17 Apoptosis of germ cells can be observed after cessation of hCG treatment in a
Paternity rates
Paternity rates among men who had undergone orchiopexy because of unilateral or bilateral cryptorchidism were compared with a control group of men who had been operated on for another reason (the controls were matched for age at operation).28, 29 When including only men who had attempted to father a child (and who had attempted at least 12 months, if they were unsuccessful), the paternity rates were significantly reduced among formerly bilaterally cryptorchid men (success rate 65% of 49 men),
Sperm concentration and adult testicular size after cryptorchidism
Approximately half of men with persistent unilateral cryptorchidism and 0% of men with untreated bilateral cryptorchidism have normal sperm concentration.38, 39 According to an older review, based on studies in which orchiopexy was usually performed between the ages of 4 and 14 years, 57% and 25% of men treated (with orchiopexy and possible hormonal treatment) for unilateral or bilateral cryptorchidism, respectively, had normal sperm concentration in adulthood.38 In the study by Taskinen and
Acquired cryptorchidism and fertility
In addition to congenital cryptorchidism, there is also acquired form of cryptorchidism. Testicular ascent may be seen in boys with a retractile testis or in boys who have previously had ipsilateral inguinal operation (entrapment of the testis into the scar).49, 50 In addition, improper elongation of the spermatic cord due to fibrous remnant of the processus vaginalis and spasticity of the cremaster muscle have been proposed as possible causes for testicular ascent.51, 52 Acquired
Summary
Different types of evidence support the current recommendation of treatment of cryptorchidism during the first year of life or later on immediately at diagnosis to optimize the fertility potential of cryptorchid patients.
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Cited by (0)
Funding Sources: This work was supported by the Academy of Finland, the Turku University Hospital, and Sigrid Jusélius Foundation.
Conflict of Interest: The authors have nothing to disclose.