Background: Cryptorchidism, or undescended testes, is the most common congenital anomaly in newborn males, with a prevalence of 2% to 9% in full-term infants. There is a current debate regarding the optimal time to perform orchidopexy.
Methods: We searched PubMed, Scopus, and Web of Science [August 2024] using terms relating to cryptorchidism, orchidopexy, and the outcomes of interest. The primary outcome was the incidence of testicular atrophy. Secondary outcomes included preoperative and postoperative testicular volume, the number of spermatogonia per tubule, and seminiferous tubular diameter. Data were analyzed using fixed- or random-effect models based on the presence of heterogeneity.  
Results: Nine studies involving 5,494 patients were included. There was no significant difference in the incidence of testicular atrophy between early and late orchidopexy groups [OR = 0.92, 95% CI [0.44 to 1.94], p = 0.83]. Early orchidopexy was associated with a significantly higher number of spermatogonia per tubule [mean difference [MD] = 0.47, 95% CI [0.33 to 0.60], p = 0.00] and greater seminiferous tubular diameter [MD = 9.92, 95% CI [3.34 to 16.40], p = 0.11].
Conclusion: Early orchidopexy had been suggested to offer better fertility outcomes. However, the current work showed that the timing of orchidopexy may not be critical in preventing testicular atrophy.