Modern Pediatrics. Ukraine. (2026).3(155): 127-138. doi: 10.15574/SP.2026.3(155).127138
Sheremetiev V. O.¹, Konoplitskyi V. S.¹, Fedus V. P.², Korobko Yu. Ye.^1
1National Pirogov Memorial Medical University, Vinnytsia, Ukraine
²Danylo Halytsky National Medical University, Ukraine

For citation: Sheremetiev VO, Konoplitskyi VS, Fedus VP, Korobko YuYe. (2026). Issues of the etiopathogenesis, classification, and terminology of cryptorchidism in children (literature review). Modern Pediatrics. Ukraine. 3(155): 127-138. doi: 10.15574/SP.2026.3(155).127138.
Article received: Dec 03, 2025. Accepted for publication: Apr 13, 2026.

Cryptorchidism is a congenital developmental anomaly characterized by the failure of one or both testes to descend into the scrotum. It is associated with an increased a risk of impaired spermatogenesis, endocrine dysfunction and testicular neoplasia, and represents a component of the testicular dysgenesis syndrome. Despite the large number of classification systems and published studies, the lack of standardized terminology and universally accepted treatment guidelines complicates the development of an optimal surgical management strategy.
Aim – to systematize current views on the etiology, pathogenesis, classification approaches, and clinical significance of cryptorchidism, and to identify problematic aspects that hinder the standardization of diagnostic and therapeutic algorithms.
Data analysis indicates that cryptorchidism has a polyetiological nature: genetic defects, maternal factors (age, gestational diabetes, smoking, exposure to endocrine disruptors), mechanical obstructions, and environmental influences may disrupt testicular migration. Two key phases of testicular descent are distinguished: the transabdominal phase (regulated by INSL3 and AMH) and the inguinoscrotal phase (androgen-dependent). Cryptorchidism has been shown to contribute to degeneration of the spermatogenic epithelium as early as two years of age and to induce autoimmune reactions affecting the contralateral testis. The role of anti-androgenic environmental contaminants capable of disrupting embryonic gonadal development is also described. Our analysis shows that despite the wide variety of classifications, none encompasses all variants of the condition, and certain states (e.g., intermittent movement of the testis between the abdomen and the inguinal canal) remain outside systematic frameworks.
Conclusions. Cryptorchidism remains one of the key issues in pediatric urology and andrology, significantly affecting male reproductive health. The lack of unified terminology, insufficient morphological evidence, and limitations of existing classifications hinder treatment standardization.
The authors declare no conflict of interest.
Keywords: fertility, cryptorchidism, undescended testis, gonad, etiology, pathogenesis, classification, orchiopexy, treatment.
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