About Testicular Function
The testes perform two functions. The first is to produce the male hormone testosterone which is secreted into the blood stream and has a wide range of effects upon the body. The other role of the testis is to produce sperm. Either one or both functions may go astray during a man’s lifetime. Since the testis has an absolute requirement for testosterone in order to make sperm, it is possible to have abnormalities in spermatogenesis with normal testosterone but not vice versa. It is extremely rare for men of reproductive age to have abnormal testosterone levels and much more common for them to have abnormalities in sperm production associated with normal testosterone levels.
What is a Diagnostic Testis Biopsy?
The most common finding amongst infertile men is abnormal sperm production in terms of numbers and quality. However, a small percentage of men have a zero sperm count known as azoospermia.
There are three causes for azoospermia:
- Insufficient hormones and this is easily established by blood tests.
- Problem in the testis producing sperm
- Blockage preventing sperm from getting out similar to a vasectomy.
The last two can sometimes be differentiated by findings in the history, physical examination or on blood tests, however, there are a significant number of times when it is still uncertain. In that case, a diagnostic testicular biopsy is performed to differentiate between obstruction and a problem inside the testis.
A diagnostic testicular biopsy consists of taking a small pea sized amount of tissue out of both testes and sending them to the pathology laboratory for examination. The tissue must be handled properly in a special way for the biopsy to be worthwhile. Thus, even though the procedure is quite simple, it is best performed at a center that has a great deal of experience with male infertility.
The management options for couples in whom the husband has a zero sperm count depend upon the exact cause. Adoption and donor insemination are always an alternative option to fixing the husband’s problem or using sperm harvested from him in combination with in vitro fertilization (IVF); test tube baby technology. Hormonal therapy is highly effective in men who have insufficient hormones. For those men who have a problem in the testis, therapies aimed at improving testicular function may be employed such as varicocele repair. The alternative is to harvest sperm from the testes (see sperm retrieval procedures).
About 50% of men with a zero sperm count have sufficient sperm production within the testes to allow fertilization of the wife’s eggs using intracytoplasmic sperm injection (ICSI) a form of IVF. The options for couples where the man has a zero sperm count due to a blockage are to repair the blockage or harvest sperm to be used in IVF.