Does bilateral undescended testis have worst testicular function than unilateral cases? A meta-analysis of adult orchidopexy patients.

Introduction: Cryptorchidism, or undescended testis (UDT), is a congenital anomaly linked to an increased risk of infertility. The laterality of UDT, whether unilateral or bilateral, may influence post-orchidopexy outcomes. This meta-analysis compares testicular function and azoospermia rates between patients with bilateral and unilateral UDT post-orchiopexy.

Materials and methods: A comprehensive literature search was performed using PubMed, ScienceDirect, and Google Scholar databases up to March 2025. Statistical analyses were conducted using Review Manager (RevMan).

Results: Ten eligible studies were included in the analysis, comprising 563 bilateral UDT post-orchidopexy and 1259 unilateral UDT post-orchidopexy cases. Populations post bilateral orchidopexy have significantly higher FSH level (MD: 3.77 UI/L [95% CI: 1.65 - 5.89]), significantly higher LH level (MD: 1.27 UI/L [95% CI: 0.27 - 2.26]), lower inhibin B level (MD: -44.86 pg/mL [95% CI: -69.58 - -20.15]), and higher frequency of azoospermia (OR 2.3 [95% CI: 1.57 - 3.37]) compared to unilateral UDT post orchidopexy.

Conclusions: Bilateral UDT post-orchidopexy exhibits poorer testicular function with significantly higher FSH and LH levels, reduced inhibin B levels, and a greater incidence of azoospermia compared to unilateral UDT post-orchidopexy.