O-138 Factors influencing sperm retrieval rate of microdissection testicular sperm extraction in nonobstructive azoospermia patients with different etiologies: a retrospective study of 3104 patients
Authors: Zhang L , Li R , Liu P , Hong K 
Published: June 2023

Abstract

Study question
What are predictors of successful sperm retrieval (SRR) with microdissection testicular sperm extraction (mTESE) in men with non-obstructive azoospermia (NOA) according to different etiologies?

Summary answer
Predictors for SRR were different in patients with various etiologies and effects of age on SRR in idiopathic NOA and KS patients were opposite.

What is known already
NOA patients due to spermatogenic dysfunction, accounting for about 60 percent of the total azoospermia cases, may have opportunities to obtain sperm by mTESE and overall SRR of mTESE in NOA patients is about 50%. There were some of predictive factors for SRR at mTESE including age, testis volume, serum follicle stimulating hormone (FSH), testosterone (T), inhibin B, anti-Mullerian hormone and testicular histopathology, while the predictive factors of SRR remains underappreciated, especially in accordance with different type of etiology. Most notably, there are some controversies about the relationship between SSR and age at mTESE surgery.

Study design, size, duration
This retrospective study involved 3104 NOA patients with different etiologies treated with the first mTESE at the Reproductive Medical Centre of Peking University Third Hospital from March 2012 to December 2022.

Participants/materials, setting, methods
3104 NOA patients were classified into seven groups according to etiologies including 1530 males with idiopathic NOA (iNOA), 763 males with Klinefelter syndrome (KS), 345 males with microdeletion of the AZFc, 177 cases with the history of cryptorchidism, 131 with a history of mumps orchitis, 89 males with cryptozoospermia and 69 cases with other causes. The end-point was the presence of one or more sperm. Multi-variable logistic regression was used to analyze sperm retrieval outcome.

Main results and the role of chance
Overall SRR was 43.46%, and there were different SRR in NOA patients with various etiologies with highest SRR of 89.31% in patients with a history of mumps orchitis and lowest SRR of 29.35% in iNOA patients. For patients with a history of mumps orchitis, there was a negative relationship between T and SRR (0.805 [0.654, 0.991] p = 0.041). For cryptozoospermia patients, shorter infertility duration was predictive for successful SRR (0.837 [0.704, 0.995], p = 0.044). Males with bigger testes had more likelihood of positive SRR (1.077 [1.005; 1.153], p = 0.035) in patients with cryptorchidism. BMI was an independent factor of SRR in AZFc-deleted patients (1.084 [1.013, 1.161], p = 0.020). For KS patients, lower male age (0.938 [0.898, 0.979], p = 0.004) and bigger testes (1.214[1.099, 1.342], p＜0.001) were predictive for successful SRR. Lower levels of FSH (0.984[0.970, 0.998] p = 0.025) and higher male age(1.079[1.050, 1.110], p＜0.001) were predictive for successful sperm retrieval in iNOA patients. So, the optimum age range of iNOA male undergoing mTESE should be 30 to 35 years old with the SRR of 29.13% when considering low SRR of iNOA males aged＜30 years (23.96%) and the negative effect of female age on ICSI outcome.

Limitations, reasons for caution
Surgeon performing mTESE maybe another predictor for SRR which is a potential selection bias. Inhibin B and Anti-Müllerian hormone weren’t included due to limited information in our database. We couldn’t verify the conclusion in more population from multicenter despite the current study with the large sample size so far.

Wider implications of the findings
Our results provide valuable information for NOA patients who want to counsel surgeons about their treatments to help patients and surgeons to perform a shared decision-making for optimal therapy methods, especially about optimal age treated with mTESE in iNOA and KS patients.

Trial registration number
not applicable