Development and validation of a nomogram for predicting sperm retrieval success in patients with non-obstructive azoospermia undergoing testicular sperm aspiration.

BACKGROUND

Non-obstructive azoospermia (NOA) is a major cause of male infertility, characterized by impaired spermatogenesis. Testicular sperm aspiration (TESA) is widely used for sperm retrieval in assisted reproduction, but predicting its success remains challenging. This study developed and validated a nomogram for predicting sperm retrieval outcomes in patients with NOA undergoing TESA.

METHODS

We retrospectively analyzed 548 patients with NOA who underwent TESA at the Andrology Department of The First Affiliated Hospital of Soochow University between January 2010 and January 2025. Patients were classified into sperm-positive (n=284) and sperm-negative (n=264) groups. Clinical, demographic, hormonal, biochemical, and imaging data were collected. Univariate analysis identified potential predictors, which were further assessed using multivariate logistic regression. Independent predictors were incorporated into a nomogram. Model performance was evaluated using calibration plots, receiver operating characteristic curve analysis, and decision curve analysis (DCA).

RESULTS

Multivariate analysis identified larger testicular volume [odds ratio (OR): 0.707/mL, 95% confidence interval (CI): 0.659-0.759/mL, P<0.001], lower follicular-stimulating hormone (FSH) levels (OR: 1.053/mIU/mL, 95% CI: 1.024-1.082/mIU/mL, P<0.001), and absence of prior hernia repair (OR: 0.373, 95% CI: 0.189-0.733, P=0.004) as independent predictors. The nomogram demonstrated good calibration (Hosmer-Lemeshow χ2 =5.1207, P=0.74) and excellent discrimination (area under the curve: 0.842, 95% CI: 0.809-0.874), outperforming individual predictors. DCA confirmed superior clinical net benefit of the model over single variables.

CONCLUSIONS

Our results suggest that the validated, noninvasive, and clinically applicable model may enhance preoperative counseling, optimize treatment strategies, and support individualized patient management.