Hormonal therapy using gonadotropin releasing hormone for improvement of fertility index among children with cryptorchidism: a meta-analysis and systematic review.

BACKGROUND/PURPOSE: Gonadotropin releasing hormone(GnRH) as an adjunct to orchidopexy for the treatment of cryptorchidism is still controversial. Present evidences were studied through a meta-analysis of comparative clinical trials.

METHOD: Systematic literature search was done up to September 30, 2013. Studies were independently appraised by two reviewers. Continuous data of fertility indices were extracted as weighted mean difference (WMD) and standard deviation (SD); while nominal data of fertility indices were extracted as relative risk (RR). Random effects model was used to analyze the pooled effect estimates. Inter-study heterogeneity and publication bias were assessed. PROSPERO Protocol registration (CRD42013004922).

RESULTS: Ten eligible studies were included. The pooled effect estimates showed that cryptorchid children treated with GnRH when compared with controls, have significantly increased germ cell per tubule (WMD: 0.35; 95% CI 0.07-0.62, P=0.01) and increased RR to have normal value of germ cell per tubule (RR: 2.86; 95% CI 1.73-4.71, P<0.0001). Inter-study heterogeneity was noted, source identified with subgroup analysis. Publication bias was not evident. No GnRH related adverse events were reported in all studies.

CONCLUSION: Evidence suggests that a subset of boys with cryptorchidism may benefit from GnRH as adjunctive to orchidopexy in improving the fertility index. However, future studies are recommended to specifically identify subgroup characteristics of cryptorchidism that will clearly benefit from the treatment.