OBJECTIVETo introduce the application of percutaneous epididymal sperm aspiration (PESA) in the differential diagnosis between obstructive and non-obstructive azoospermia, and to investigate the association of the results of PESA with testis volume and the level of serum follicle stimulating hormone (FSH).

METHODSA total of 118 patients with diagnosed azoospermia were included. Their testis volume was measured by model method, the serum gonadal hormone level examined by chemoluminescence assay, and the epididymal fluid obtained by puncturing the head of the epididymis with a size-7 butterfly needle.

RESULTSSperm was found in the epididymal fluid in 60 of the patients, 56 with normal and 4 with smaller testis volume, and 55 with normal and 5 with higher FSH level. No sperm was detected in the other 58 cases, 34 with normal and 24 with smaller testis volume, and 38 with normal and 20 with higher serum FSH level. The rate of successful PESA was significantly higher in patients with normal testis volume or normal serum FSH level than in those with smaller testis volume (P < 0.05) or higher serum FSH level (P < 0.05).

CONCLUSIONPESA is a quick, convenient and effective method for the differential diagnosis between obstructive and non-obstructive azoospermia.