In azoospermia, the diagnostic test which can distinguish between testicular failure and obstruction of Vas deferens is :

Ans. is a i.e. Estimation of FSH level Upto 10% of sub feile men have endocrinologic abnormalities. Routine testing for endocrine dysfunction is not indicated but should be carried out in those men with oligospermia or azoospermia. FSH, levels can distinguish between Testicular, Pretesticular and Post testicular cause of infeility in males. Hormone level Inference High FSH & Low testosterone Normal FSH with azoospermia Low FSH with No response to GnRH Low FSH with response to GnRH therapy / low FSH & low testosterone Raised LH with low Testosterone Testicular failure Obstructive lesion in the Vas or epididymes Pituitary failure Hypothalmic failure / Kallman syndrome Leydig cell dysfunction Also know : Testicular Biopsy : Generally not recommended. Indicated in cases of azoospermia with Normal FSH and inconclusive seminal markers to distinguish between a failure of spermatogenesis and obstruction of ouflow tract. Vasography : Demonstrates proximal vas deferens obstruction. Trans Rectal ultrasonography with seminal vesiculo graphy : Demonstrates Ejaculatory duct obstruction. Doppler Study / Scrotal thermo graphy : Demonstrates subclinical varicocele.