We talk a lot about women and female hormones when it comes to fertility, but what about the men?

Is more testosterone better? Does it make the sperm super?

Actually, the contrary occurs. Testosterone is very important for men as it is responsible for normal libido, muscle tone, feeling of well being and sperm health. But, if excess testosterone is taken in the form of an injection or gel/cream, it can actually cause infertility but impairing or eliminating sperm production.

The reason for this is that testosterone supplementation can cause supra-physiologic levels of testosterone in the blood stream and these can shut down the production of some important hormones by the brain that stimulate the production of sperm. Men on testosterone supplements often end up with no sperm in the ejaculate.

It can take months or even years (sometimes never) for the sperm production to return to normal even after stopping the testosterone supplements.

It makes us cringe when a couple comes in for an infertility evaluation and the male partner tells us that he has been on testosterone because of fatigue and “low testosterone “ levels. This is probably one of the worst things to do for a man if fertility is desired.

Body builders who intentionally take anabolic steroids to build muscle mass are especially prone to azospermia(no sperm in the ejaculate). So, to the men out there, never start testosterone supplements without a very good reason and talking to an infertility specialist.

Primary care doctors are unfortunately not all aware of this effect of testosterone pertaining to fertility. If testosterone supplementation has to be initiated for whatever reason, then it may be worth considering freezing some semen specimens prior to starting therapy.