Endocrine stimulation in men with non-obstructive azoospermia and low serum testosterone prior to micro-TESE: hormonal response as a predictor of sperm retrieval.

BACKGROUND

Hormonal treatment and response as a predictor of sperm retrieval prior to microdissection testicular sperm extraction (micro-TESE) are not well established in the current literature. This study aimed to investigate the hormonal response as a predictor of sperm retrieval among men with nonobstructive azoospermia (NOA).

METHODS

Seventy-seven consecutive patients who had testosterone levels ≤ 14 nmol/L were treated medically with an aromatase inhibitor or recombinant human chorionic gonadotropin (rec-hCG) prior to micro-TESE and were included. Thirty-four (44.2%) had unexplained NOA (UNEX), 25 (32.5%) had Klinefelter syndrome (KS), 8 (10.4%) had a history of cryptorchidism (UDT), 4 (5.2%) had microdeletion of the Azoospermia factor C (AZFc), and 6 (7.8%) were treated previously with chemotherapy. Baseline and post-treatment serum hormonal levels were documented. Pre-op testosterone levels were entered into binary logistic regressions with age, Follicle-stimulating hormone (FSH), and Luteinizing hormone (LH) levels to test for significance with sperm retrieval. We then built logistic regression models to identify predictors of successful surgical sperm retrieval (SSR).

RESULTS

Forty-five patients (58%) had successful retrieval. In 32 patients (42%), no sperm was retrieved. Both the mean pre-op testosterone and the mean testosterone change between the two groups were significant (p = 0.02 and p = 0.011, respectively). Receiver operating characteristic (ROC) analysis demonstrated an area under the curve (AUC) of 0.785 (95%CI = 0.685-0.886, p < 0.001). The Youden index coefficient was calculated for KS and UNEX. The cut-off point for KS was established at 0.764 (sensitivity = 0.875, false positive rate [FPR] = 0.111), and 0.215 for UNEX (sensitivity = 0.438, FPR = 0.222). We also observed a correlation between age and SSR (p = 0.05). In KS patients, SSR was determined by pre-op testosterone levels irrespective of age.

CONCLUSION

Pre-operative hormonal response is a predictor for SSR in NOA patients who were treated medically. This data may help during pre-operative counselling.