Brief Answer: Abnormality of pituitary suspected Detailed Answer: Hello, Thanks for posting your query on HealthCareMagic. Testosterone is the male hormone responsible for development of male external genitalia and spermatogenesis (formation of sperms by the testis). Testosterone is indirectly controlled by pituitary gland. The pituitary gland secretes FSH which in turn stimulates the synthesis of testosterone. In your case the testosterone levels are low and the testicular biopsy is absence of sperms and no spermatogenesis. With low testosterone levels, some abnormality of the pituitary gland is suspected. You need to consult an endocrinologist for further work up. Further management can be planned once the cause is found out. If you have more queries, I will be glad to answer. Dr Shailja P Wahal

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