What is hypogonadism?
Hypogonadism refers to a medical condition in which the testicles do not produce enough sex hormones or their normal function is impaired. In men, this primarily affects the production of testosterone, but can also impair sperm production.
Hypogonadism is one of the most common causes of a testosterone deficiency. Depending on whether the cause lies directly in the testicles or in the hormonal control centers of the brain, doctors distinguish between different forms of the disease.
Hypogonadism can be congenital or develop later in life. Symptoms range from loss of libido and fatigue to reduced muscle mass or fertility problems.
What forms of hypogonadism are there?
Generally, doctors distinguish two main forms of hypogonadism.
Primary hypogonadism
In primary hypogonadism, the cause lies directly in the testicles. Despite sufficient hormonal stimulation, they produce too little testosterone or sperm.
Typically, the hormones LH and FSH are elevated, as the body attempts to compensate for the reduced hormone production.
Secondary hypogonadism
In secondary hypogonadism, the cause lies in the hypothalamus or the pituitary gland. These produce too little GnRH, LH, or FSH, which means the testicles are not sufficiently stimulated to produce testosterone.
In this case, the concentrations of LH and FSH are usually low or at the lower end of the normal range.
What can cause hypogonadism?
Hypogonadism can be caused by numerous diseases or external factors.
The most common causes include:
- age-related changes
- genetic disorders
- testicular diseases
- surgeries or injuries to the testicles
- pituitary or hypothalamic disorders
- chronic diseases
- severe obesity
- certain medications
- hormonal imbalances
Chronic stress, sleep deprivation, or severe obesity can also affect the hormonal regulatory system and contribute to functional hypogonadism.
What symptoms occur in hypogonadism?
Since hypogonadism is often associated with a testosterone deficiency, typical symptoms usually develop.
These include, among others:
- reduced libido
- erectile dysfunction
- fatigue and exhaustion
- reduced muscle growth
- increased body fat
- reduced physical performance
- concentration problems
- depressive mood
- reduced beard growth
- fertility problems
Which symptoms occur and how pronounced they are depends on several factors, including age, the cause, and the extent of the hormone deficiency.
How is hypogonadism diagnosed?
The diagnosis is based on a combination of symptoms, physical examination, and laboratory values.
Generally, the following parameters are determined, among others:
- Total testosterone
- Free testosterone
- LH
- FSH
- SHBG
- Estradiol
- Prolactin
Depending on the findings, further tests may be necessary, such as imaging of the pituitary gland or genetic testing.
Since testosterone levels fluctuate throughout the day, the blood sample is ideally taken in the morning.
How is hypogonadism treated?
Treatment is tailored to the cause of the hypogonadism.
If there is a persistently low testosterone level with corresponding symptoms and no contraindications exist, testosterone replacement therapy (TRT) may be considered.
However, if the patient wishes to have children, other treatment strategies are often chosen to preserve or promote the body's own testosterone production and sperm formation as much as possible.
In addition, possible contributing factors such as obesity, sleep deprivation, or certain medications should be considered and, if possible, treated.
Can hypogonadism be reversed?
Whether hypogonadism can be reversed depends on the cause.
Functional hypogonadism, for example, can improve through weight loss, regular physical activity, or the treatment of an underlying medical condition.
However, if there is permanent damage to the testicles or the hormonal control centers, long-term treatment is often required.
Conclusion
Hypogonadism describes impaired testicular function with insufficient production of testosterone or sperm. Depending on whether the cause lies in the testicles themselves or in the hormonal control centers of the brain, a distinction is made between primary and secondary hypogonadism.
Careful diagnosis with hormone analysis is crucial to identify the cause and initiate the appropriate treatment. Depending on the findings, both targeted treatment of the underlying medical condition and testosterone replacement therapy may be considered. Our article Bone Health in Hypogonadal Men shows why untreated hypogonadism can also weaken the bones.