Interest of pentoxifylline in ICSI with frozen–thawed testicular spermatozoa from patients with non-obstructive azoospermia

Selection for intracytoplasmic sperm injection (ICSI) of viable frozen-thawed testicular spermatoza obtained from patients suffering from non-obstructive azoospermia is very often long, difficult and sometimes impossible. The purpose of this study was to determine if the use of pentoxifylline (PF) could facilitate this selection in stimulating sperm motility. From January 2000 to December 2004, 108 ICSI cycles with non-obstructive azoospermia were performed. From these 108 cycles, in 64 cycles where no motile spermatozoa were observed or when the time search per spermatozoa was above 20 min, 1.5 mmol/l PF was used for 10 min, whereas the 44 other ICSI cycles were performed using spontaneously motile spermatozoa (control group). In all cases, PF either initiated the motility when no motile spermatozoa were observed, or stimulated the motility, reducing dramatically the time search per spermatozoa. The total fertilization rate was 54.2% versus 66.7% in the control group (P < 0.02). Twenty-nine pregnancies out of the 64 PF cycles (45.3% per cycle) occurred, including 20 deliveries of 23 healthy children and eight ongoing pregnancies, whereas 12 pregnancies were obtained in the control group (27.3% per cycle), including nine deliveries of 13 healthy children. In conclusion, in 100% of cycles pentoxifylline allows the selection of viable frozen–thawed testicular spermatozoa with the same outcome after ICSI as that observed with fresh ejaculated spermatozoa.