Hormone changes in men that are related to aging.

Andropause is a term used to describe sex hormone changes in aging men. In particular, the hormone testosterone declines over a period of many years. The consequences of that decline aren't always clear. A man's testosterone level drops about 1% a year after age 40. But most older men still have testosterone levels within the typical range.

In some cases, low testosterone may not cause any symptoms. In others, it may lead to lower sexual desire and activity; problems with erections; breast discomfort; height loss; easily broken bones; and hot flushes or sweats. Symptoms also can include low energy and motivation; depressed mood; sleep problems; lower muscle bulk and more body fat.

Recommendations vary on testosterone therapy for age-related low testosterone. For some men, testosterone therapy relieves symptoms. For others, the benefits aren't clear, and there are possible risks. Testosterone therapy might stimulate growth of some cancers. It also may raise the risk of heart attack and stroke and lead to blood clots in veins.