Comparison of Effects of Chorionic Gonadotropin Alfa and Anastrozole on Sperm Retrieval Rate in Patients with Non-Mosaic Klinefelter Syndrome Following Microdissection Testicular Sperm Extraction

Background and Objectives: This study aimed to compare the effects of choriogonadotropin alfa and anastrozole treatments on the success of sperm retrieval in patients with Klinefelter syndrome (KS) undergoing micro-TESE at our clinic. Materials and Methods: We conducted a retrospective review of a cohort including patients with non-mosaic KS who underwent micro-TESE for fertility treatment at the Reproductive Medicine Center of our university hospital. This study included 43 patients who had not received exogenous testosterone therapy prior to or during the procedure. Before surgical sperm retrieval, all patients received either choriogonadotropin alfa or anastrozole treatment based on their preference. Micro-TESE was performed on all patients after three months of treatment. Results: The overall SRR in the cohort post-micro-TESE was found to be 32.6%. There was a significant increase in post-treatment testosterone levels compared to pre-treatment levels. Upon dividing patients into two groups based on whether sperm was successfully retrieved, we observed significant improvements in testosterone levels in both groups following treatment. In the group presenting with successful sperm retrieval, 28.6% of patients had received choriogonadotropin alfa, while 71.4% had received anastrozole. No statistically significant difference was found between treatment groups in terms of micro-TESE success. Both choriogonadotropin alfa and anastrozole treatments resulted in significant improvements in testosterone levels following treatment compared to pre-operative levels. Furthermore, in the choriogonadotropin alfa group, there were significant decreases in follicle-stimulating hormone and luteinizing hormone levels, as well as a significant increase in estradiol levels after treatment. Post-treatment E2 levels were significantly lower in the anastrozole group than in the choriogonadotropin alfa group (p = 0.032), while the mean testicular volume was statistically significantly lower in the choriogonadotropin alfa group. Conclusions: This study suggests that anastrozole treatment before micro-TESE in patients with KS yields more successful results in terms of the SRR compared to choriogonadotropin alfa treatment.