@Johnathant I don't know how useful this will be for you to know, but my husband has sperm maturation arrest. All tests showed normal but TESA, biopsy and mTESE found no mature sperm. His urologist asked about his history of radiation exposure as a possible cause, and said that even lots of xrays in the area as a child could cause this kind of problem. We used a sperm donor. My advice would be to line up the mTESE ASAP if you know you want it - you can drive yourself mad trying to interpret the numbers from the tests. Been there!