Notice: Users may be experiencing issues with displaying some pages on stanfordhealthcare.org. We are working closely with our technical teams to resolve the issue as quickly as possible. Thank you for your patience.
Men who have low testosterone do not make enough of the male hormone called testosterone. This hormone allows men to produce sperm and to develop and keep normal physical male traits. Low testosterone is also called testosterone deficiency or hypogonadism.
Low testosterone can lead to problems such as loss of sex drive, erection problems, infertility, and weakened bones.