Systematic review and meta-analysis on the effect of adjuvant gonadotropin-releasing hormone agonist (GnRH-a) on pregnancy outcomes in women with endometriosis following conservative surgery

Background: Endometriosis frequently results in pain and infertility. While conservative surgery offers some relief, it often falls short of ensuring satisfactory pregnancy outcomes. Adjuvant GnRH-a is administered post-surgery to mitigate recurrence; however, its impact on pregnancy outcomes remains debated. This study endeavors to assess the efficacy of adjuvant GnRH-a in enhancing pregnancy outcomes post-conservative surgery in endometriosis patients. Methods: Databases including PubMed, Embase, the Cochrane Library, Medline (Ovid), Web of Science, and Scopus were rigorously searched up to 02 August 2023, without linguistic constraints. Identified articles were screened using strict inclusion and exclusion criteria. Evaluated outcomes encompassed pregnancy rate, live birth rate, miscarriage rate, ectopic pregnancy rate, multiple pregnancy rate, mean postoperative pregnancy interval, recurrence rate, and adverse reaction rate. The Cochrane risk of bias tool and the Jadad score evaluated the included studies’ quality. Subgroup and sensitivity analysis were implemented to analyze the pooled results. A meta-analysis model expressed results as standardized mean difference (SMD) and Risk ratio (RR). Results: A total of 17 studies about 2485 patients were assimilated. Meta-analysis revealed that post-surgery, the GnRH-a cohort experienced a marginally elevated pregnancy rate (RR = 1.20, 95% CI = 1.02–1.41; P = 0.03) and a reduced mean time to conceive (RR = -1.17, 95% CI = -1.70- -0.64; P < 0.0001). Contrarily, other evaluated outcomes did not exhibit notable statistical differences. Conclusions: Incorporating adjuvant GnRH-a following conservative surgery may be deemed beneficial for women with endometriosis, especially before Assisted Reproductive Technology (ART). Nonetheless, owing to pronounced heterogeneity, subsequent research is warranted to substantiate these potential advantages conclusively. Registration number: CRD42023448280.