We have had a rash of new infertility patients whose husbands had been put on testosterone by their primary care providers. The usual story is that the husband complains of fatigue, maybe during a routine visit. The doctor (or in one case the nurse practitioner) gets a testosterone level, which is just below the normal range. The man gets put on testosterone. No one bothers to ask if he is trying to father a child. The couple subsequently shows up in our office with infertility, and the semen analysis shows ... no sperm.
The other story we hear occasionally is that the husband isn't taking any prescription meds, but his friend at the gym is providing him with a "nutritional supplement", which turns out to be a testosterone-like substance. We have learned to ask about this whenever we see an abnormal semen analysis.
Testosterone isn't a great contraceptive - only about 80% of men will develop azoospermia. I wonder if there is some sort of recent drug company campaign that is leading to this recent increase in testosterone prescriptions.
My partner Dr. Malizia recently saw an even more bizarre infertility case. The wife was getting testosterone from one of those "natural hormone replacement" clinics you see advertised on TV.
Please don't take testosterone if you are trying to have a baby!