Eligibility for the medical therapy among men with non-obstructive azoospermia—Findings from a multi-centric cross-sectional study

Background: Existing literature does not provide accurate epidemiological data regarding the true prevalence of men with non-obstructive azoospermia (NOA) who would be eligible for hormonal optimization therapy, according to specific pre-treatment criteria. Objectives: To investigate the characteristics of those men with NOA who would qualify for the medical therapy prior to any SR procedure in a large multi-centric cross-sectional study. Materials and methods: Complete data from 1644 NOA patients seeking medical help for primary infertility at three tertiary referral centers from USA, Brazil, and Italy were analyzed. Baseline serum hormone levels were collected for all patients. NOA was confirmed after two consecutive semen analyses. Genetic tests, including karyotype analysis and Y microdeletions, were performed on all patients. Patients with secondary hypogonadism (total testosterone (T) levels less than 300 ng/dL and luteinizing hormone (LH) levels less than 8 mIU/mL) were earmarked as potential candidates for receiving clomiphene citrate (CC) and/or human chorionic gonadotropin (hCG). Patients with a T to 17β-estradiol (E2) ratio < 10 were classified as eligible for aromatase inhibitors (AIs) therapy (e.g., anastrazole). A third sub-cohort was created by combining the criteria of the first two sub-cohorts. Descriptive statistics was used to detail overall characteristics and differences between the different sub-cohorts. Results: Among the 1,644 men, 28% (n = 460) had T < 300 ng/dL and LH < 8 mIU/mL, thereby being potentially suitable for CC and/or hCG, while 37% (n = 607) had a T to E2 ratio < 10 thus potentially suitable for AIs. Lastly, 17.7% (n = 280) met the criteria for potential eligibility for both CC and/or hCG and AIs. Conclusions: Findings from this multicentric cross-sectional study reveal that about 30% of men with NOA were eligible for hormonal treatment with CC and/or hCG while 37% were found to be potential candidates for AIs, and 17% for both therapies. Therefore, these findings show that a only a small subset of NOA patients can benefit from medical therapy prior to considering any SR procedures.