Here is one thing I found online:

While the biopsy is an easy test to perform, it is difficult to interpret properly, unless done by an expert. The doctor looks for evidence of sperm production in the seminiferous tubules. In some cases, there is no sperm production at all (absent spermatogenesis); or the sperm production is arrested at a particular stage (maturation arrest). This implies testicular failure, which is usually irreversible, and there is no treatment for this malady. The key question is whether there is partial testicular failure; or whether the testicular failure is complete, which is why examining multiple areas of the testes is important. Men with complete testicular failure have no sperm production at all in the entire testes. Men with partial testicular failure will have a few areas of their testes which still produce sperm normally. These sperm can be used for TESE-ICSI treatment. However, their testicular sperm production is so poor , that the testicular sperm do not reach the ejaculate, as a result of which the sperm count is zero.

So . . . it does mean there should be good sperm in there as is, even if medicine doesn't improve the situation. So, I think that is FANTASTIC news!

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