Introduction & Objective: Male factor is the major cause of infertility in 20% of cases (WHO). There are known etiologies for 70% of cases .However, 30% of infertility cases are of idiopathic origin. The Y chromosome and micro deletion of the long arm of the Y chromosome (Yq) in three regions (AZFa, AZFb ,AZFc ) are associated with spermatogenic failure and is a major etiology for oligo and azoospermia in infertile men. With the advent of assisted reproductive technology and intracytoplasmic sperm injection, knowledge about the various factors leading to spermatogenic impairment is one of the most important aspects of scientific research. Therefore, this study was designed to identify the frequency of microdeletions of Yq in azoospermia and oligozoospermia males refered to Hamadan Fatemieh hospital.

Materials & Methods: 56 infertile males with non obstructive oligozoospermia and azoospermia and without any cytogenetic abnormality and 44 fertile men with normal cytogenetic were included in this case-control study. Semen analysis was done is each case to determine the spermatogenic statuse. Patients with normal karyotyping were analyzed for determination of microdeleton in Y chromosome in the AZFa, AZFb and AZFC regions with multiplex PCR method. The sequence tagged sites (STS) primers sY84, sY86 (AZFa) sY127, sY134 (AZFb) sY254, sY255 (AZFc) were used for each case.

Results: In this study the rate of mutation were 1.87% in oligo and azoospermia infertile men, 4% in azoosperm and 0% in oligospermia patients. Of 56 cases, 1 case showed deletion in AZF region ,1 deletion was in AZFa(sY84), 2 deletions in AZFb (sY127, sY134), and 1 dele-tion in AZFc (sY254). That had 1 deletion in AZF a (sY84), 2 deletions in AZFb (sY134, sY127) , and 1 deletion in AZFc(sY254). No microdeletions were seen in the SRY gene and no microdeletions were found in men in the control group.

Conclusion: Our results emphasize that Y chromosome microdeletion analysis should be carried out in all patients with idiopathic azoospermia or severe oligospermia who are candidates for intracytoplasmic sperm injection. Moreover, it is highly suggested to perform further studies to discover the numerous etiologies of idiopathic male infertility.