Age does not adversely affect sperm retrieval in men undergoing microdissection testicular sperm extraction

Abstract

Objective: To evaluate the effect of male age on the outcome of microdissection testicular sperm extraction (micro-TESE) and assisted reproductive technology.

Design: Clinical retrospective study.

Setting: Center for reproductive medicine at a tertiary university hospital.

Patient(s): One thousand sixty-seven men with nonobstructive azoospermia.

Intervention(s): Micro-TESE, with intracytoplasmic sperm injection when sperm found.

Main outcome measure(s): Sperm retrieval and clinical pregnancy.

Result(s): Sperm were successfully retrieved by micro-TESE in 605 men (56.6%) overall. Sperm retrieval rates (SRRs) were higher in men ≥50 years old than men <50, (73% in men ≥50, 56% in men <50). Of the 44 men ≥50 years old, men who had successful micro-TESE had larger mean testis volume (20.8 cc vs. 12.5 cc), a higher frequency of hypospermatogenesis (5.6% vs. 0%), and a lower frequency of Sertoli cells only (12.5% vs. 80%) on diagnostic biopsy. Clinical pregnancy rates were lower in partners of men ≥50 than in partners of men <50 (48% in men <50, 25% in men ≥50). Lower pregnancy rates may be at least partially explained by older female partners for men ≥50 compared to men <50 (mean age 38.0 vs. 36.2 years). Sperm were successfully retrieved across all age groups, and there was no upper male age limit above which sperm could not be retrieved.

Conclusion(s): Overall, SRRs in men undergoing micro-TESE are not negatively affected by age. Despite successful sperm retrieval in older men with micro-TESE, couples have the best chance of clinical pregnancy with a female partner <35 years old. Some older men with azoospermia may have secondary azoospermia with hypospermatogenesis, explaining the high sperm retrieval rate.

Keywords: Testis; age; biopsy; microsurgery; retrieval.