General overview of the service:

Testosterone plays a key role in the development of male reproductive tissues such as the testis and prostate as well as promoting increased muscle, bone mass, and the growth of body hair.
Testosterone level peaks during early adulthood. Once you reach age 30, testosterone levels slowly decline by approximately 1% a year.
This is a normal part of aging.
Low testosterone (low-T) is underproduction or lack of production of testosterone in men and women. Causes of low-T include chronic medical conditions such as diabetes, infections, obesity or other hormonal conditions.
Men who have difficulty with low sex drive, erections, and other changes should seek a health practitioner’s advice on their condition. Low testosterone might be the root of the problem in some cases.