Morphology of testicular spermatozoa obtained by testicular sperm extraction in obstructive and nonobstructive azoospermic men and its relation to fertilization success in the in vitro fertilization-intracytoplasmic sperm injection system

The aim of the present study was to evaluate the morphology of testicular s permatozoa by 3 different determinants. Sperm cells were obtained and their morphology was evaluated from 27 testicular sperm extraction (TESE) operat ions, of which 20 men had nonobstructive azoospermia and 7 had obstructive azoospermia. In 17 cases, 2 biopsies were obtained from 2 different locatio ns of the testis. Only mature spermatozoa presenting full-grown tail (tail dimension about 10-fold greater than the head dimension) were counted. Thre e characteristics of sperm morphology were evaluated: head dimensions, and acrosome and midpiece irregularities. The percentage of sperm cells with no rmal morphology (considering the 3 characteristics) in specimens from patie nts with obstructive and nonobstructive azoospermia were 47% +/- 4.6% and 2 9 +/- 1.8%, respectively (P < .01). The percentage of spermatozoa with norm al head dimensions were 76% +/- 3.2% and 63% +/- 2.6% (P > .05), those with normal acrosome were 58% +/- 4.6%, and 41% +/- 3.4% (P < .05), and those w ith normal midpiece were 74% +/- 4.1% and 67% +/- 1.6% (P > .05), in obstru ctive and nonobstructive azoospermia, respectively. No significant differen ces were observed in sperm morphology between different locations of the te stis. Sperm morphological characteristics were not associated with fertiliz ation rate in intracytoplasmic sperm injection (ICSI). Follicle-stimulation hormone and luteinizing hormone were inversely correlated with normal morp hology of testicular spermatozoa (r = -0.49 and r = 0.47, respectively; P < .05). It can be concluded that a relatively high portion of testicular spe rm are morphologically normal. The higher rate of normal spermatozoa in obs tructive azoospermia compared with nonobstructive spermatozoa suggests that the factors leading to azoospermia may affect testicular sperm morphology. The morphological characteristics of testicular sperm do not affect fertil ization rate in ICSI.