Severe Testicular Atrophy does not Affect the Success of Microdissection Testicular Sperm Extraction

Purpose: Men with azoospermia and severe testicular atrophy may be counseled to avoid sperm retrieval due to perceived limited success. We evaluated the outcomes of microdissection testicular sperm extraction in men with severe testicular atrophy (volume 2 ml or less). Materials and Methods: We reviewed the records of 1,127 men with non-obstructive azoospermia who underwent microdissection testicular sperm extraction followed by intracytoplasmic sperm injection. They were classified into 3 groups based on average testicular volume, including 2 ml or less, greater than 2 to less than 10 and 10 or greater. Sperm retrieval, clinical pregnancy and live birth rates were calculated. Clinical features evaluated included age, follicle-stimulating hormone level, cryptorchidism history, Klinefelter syndrome, varicocele and testicular histology on diagnostic biopsy. Results: Testicular sperm were successfully retrieved in 56% of the men. The sperm retrieval rate in those with a testicular volume of 2 ml or less, greater than 2 to less than 10 and 10 or greater was 55%, 56% and 55%, respectively. Clinical pregnancy and live birth rates were similar in men in the 3 groups who underwent sperm retrieval (55.2%, 50.0% and 47.0%, and 47.2%, 43.0% and 42.2%, respectively). Of the 106 men with an average testis volume of 2 ml or less those from whom sperm were retrieved were younger (31.1 vs 35.2 years) and more likely to have a history of Klinefelter syndrome (82.2% vs 55.6%) than men in whom sperm were not found (p < 0.05). Men in this group had a higher prevalence of Klinefelter syndrome than men with a testis volume of greater than 2 ml (72.6% vs 5.3%, p < 0.0001). Men younger than 30 years with Klinefelter syndrome had a higher sperm retrieval rate than men older than 30 years without Klinefelter syndrome (81.8% vs 33%, p < 0.01). There was no cutoff point for age beyond which sperm could not be retrieved in men with small testes. On multivariable analysis younger age was the only preoperative factor associated with successful sperm retrieval in men with small testes (2 ml or less). Conclusions: Testicular volume does not affect the sperm retrieval rate at our center for microdissection testicular sperm extraction. Of men with the smallest volume testes those who were younger with Klinefelter syndrome had the highest sperm retrieval rate. Severe testicular atrophy should not be a contraindication to microdissection testicular sperm extraction.