What is hypogonadism?
Hypogonadism is a medical condition in which the body produces insufficient testosterone, classified as either primary (testicular failure) or secondary (hypothalamic or pituitary dysfunction).
Hypogonadism occurs when the testicles fail to produce adequate levels of testosterone, the primary male sex hormone. The condition is divided into two clinical categories based on where the problem originates in the hormone pathway.
Primary hypogonadism involves direct testicular dysfunction. The testes themselves cannot manufacture enough testosterone despite normal signaling from the pituitary gland. Causes include testicular injury, infection, genetic disorders, or age-related decline. Blood tests show low testosterone with elevated luteinizing hormone (LH) and follicle-stimulating hormone (FSH) as the body attempts to compensate.
Secondary hypogonadism stems from inadequate signaling from the brain. The hypothalamus or pituitary gland fails to produce sufficient LH and FSH, which normally trigger testosterone production in the testes. This pattern can result from obesity, sleep apnea, chronic illness, medications, or injury to the pituitary region.
Both types produce similar symptoms: low energy, reduced libido, erectile dysfunction, mood changes, and loss of muscle mass. Diagnosis requires blood work measuring testosterone, LH, and FSH levels. Once confirmed, hypogonadism is the clinical foundation for testosterone replacement therapy (TRT). Men and their clinicians must establish the type and underlying cause before selecting a treatment approach, whether pharmaceutical, lifestyle-based, or combined. An understanding of which form a patient has guides appropriate management and helps providers determine the right treatment strategy.