Written by Philip Cheng, MD on September 12, 2024
Testosterone deficiency is also known as low testosterone, “low T,” hypogonadism, and hypoandrogenism. Testosterone deficiency is common, affecting approximately 4-5 million men in the United States. Beginning around the age of 30, testosterone levels in men often start to decline. About 7% of men in their 50s have low testosterone and the incidence increases with age.
What is testosterone?
Testosterone is one of the hormones naturally produced by both men and women, but is more pronounced in its effects for men, where it is produced mainly in the testicles. Testosterone is critical for sexual development, fertility/sperm production, sex drive/sexual function, and building bone and muscle mass.
Signs and symptoms of low testosterone
Despite being known as a sex hormone, testosterone is essential for more than just sexual function; it is critical for normal functioning and development of the male body. Low testosterone can result in a variety of signs and symptoms, such as low libido, erectile dysfunction, reduced semen volume, fatigue, difficulty with exercising and gaining muscle, weight gain, increased body fat, decreased bone density, mood swings, low motivation, impaired concentration/memory, difficulty with sleep, lower sperm counts, smaller than usual penis or testicles, and anemia.
How does testosterone impact male fertility?
A delicate hormonal balance is necessary for optimal sperm production, with testosterone playing a crucial role. Having low testosterone can lead to lower sperm counts, and thus, infertility. It may seem counterintuitive, but exogenous testosterone given through medication, is actually problematic for fertility. The body will sense an excess of testosterone and shut down the testes, leading to lower or absent sperm production.
What causes testosterone deficiency?
Apart from the natural decline with advancing age, there are specific conditions that can cause low testosterone in men of all ages, even in young men and children. There are two types of hypogonadism, primary and secondary.
- Primary hypogonadism: This is caused by underactive testes. The problem arises because the testicles don’t produce the levels of testosterone required for optimum health and growth. This can be caused by an inherited characteristic or result from injury or illness. Some conditions include undescended testicles, Klinefelter syndrome, and hemochromatosis. Some types of injury, as opposed to inherited conditions, that can cause primary hypogonadism include physical injury to the testicles, mumps orchitis, and a history of cancer treatment, such as chemotherapy and radiation.
- Secondary hypogonadism: Secondary hypogonadism is when the cause of low testosterone is not directly related to the testicles. It results from damage to the pituitary gland or hypothalamus in the brain, which control hormone production by the testicles. It can be the result of either inherited conditions or acquired circumstances. Inherited causes include disorders of the pituitary gland resulting from drugs, kidney failure, or tumors, Kallmann syndrome, inflammatory diseases like tuberculosis, and HIV/AIDS. Acquired conditions that can lead to secondary hypogonadism include normal aging, obesity, and medications, such as opioids and anabolic steroids.
How to diagnose testosterone deficiency
Generally, a diagnosis of hypogonadism depends on two factors: a measurement of low testosterone levels in the blood and the display of some of the signs and symptoms of low testosterone. Confirmation is needed with two separate blood tests in the early morning on non-consecutive days. This is because testosterone levels typically fluctuate throughout the day but are at their peak in the morning. In general, a diagnosis requires symptoms of hypogonadism and levels below 300 ng/dL. Some patients do have normal total testosterone levels but can be treated if their free testosterone or bioavailable testosterone levels are low.
Treatment for testosterone deficiency
In general, things that are good for your health, such as eating healthy foods and maintaining a body mass index in the normal range can help boost testosterone levels.
Certain foods that are rich in nutrients such as vitamin D and zinc can help boost testosterone. Some examples include fish, low-fat milk enriched with vitamin D, egg yolks, oysters and shellfish, and legumes.
However, diet alone often is not a cure for hypogonadism. Medication is often necessary and there are many different formulations of testosterone replacement. It is important to keep in mind that almost all testosterone formulations will suppress sperm production.
- Testosterone injections: Regular (typically weekly) injections can replace natural testosterone levels. However, injections should be used cautiously as they almost always suppress sperm production.
- Transdermal (topical) testosterone: This involves the application of testosterone gel or patches on the skin. It’s a non-invasive method to supplement testosterone but shares the same risk of suppressing sperm production.
- Testosterone pellets: Implanted under the skin, typically near the hip or buttocks, these pellets gradually release testosterone and last for about four months. They provide a steady hormone release but have the same risks as injections and topical testosterone with regards to suppressing sperm production
- Oral testosterone: Oral formulations of testosterone replacement require taking a pill twice a day. These formulations are effective but may not get levels as high as injections.
- Testosterone nasal gel: This is the only formulation of testosterone that tends to preserve sperm production because it is very short-acting. The downside is that it needs to be administered through each nostril two to three times a day.
- Clomiphene citrate (Clomid), anastrozole (Arimidex), and human chorionic gonadotropin (hCG): These medications work differently from testosterone supplements. Instead of supplementing testosterone, they stimulate the testicles to produce more testosterone and can therefore preserve or even improve sperm production. Unfortunately, these medications are not effective in everyone. Some men will not have a boost in testosterone levels and others may have a boost but may not experience symptomatic improvement.
Who can diagnose and treat testosterone deficiency?
Your best option is to see a urologist who specializes in hypogonadism and male infertility, also known as a reproductive urologist. These doctors are specifically trained to diagnose and treat low testosterone and related conditions.
While the tests could be administered by your primary care physician (PCP), many PCPs are not adequately trained to diagnose and treat testosterone deficiency. They also may not be familiar with all of the different hormone medications available, especially the fertility-friendly options. Unfortunately, a lot of physicians who prescribe testosterone replacement therapy do not effectively counsel patients about how these medications can suppress sperm production and what other options are available. Thus, these patients often end up seeing a reproductive urologist for further management.
If you’re a Progyny member, please contact your dedicated Patient Care Advocate (PCA) for more information.