While it’s true testosterone plays a role in reproductive success, it is also true that it can have somewhat of a reverse effect when the hormone is introduced from outside the body. We know this may sound counterintuitive — after all, when this hormone is lacking in the body, men can have issues with everything from libido to sperm development.
With that said, it’s important to understand that the link between testosterone and fertility is actually a little more complicated, especially when it comes to testosterone supplementation and therapy. Continue reading to get a closer look at this hormone, why people take testosterone, and how testosterone use can affect fertility.
Testosterone is a primary reproductive hormone produced naturally by the biological male body. While testosterone is also produced by the ovaries in women, the levels are much less profound. In men, testosterone is produced by the testes and adrenal cortex. This major sex hormone plays a role in a long list of processes in the male body, including:
While not completely understood, testosterone may also play a role in things like cognition, energy levels, and mood. This is indicated by the fact that most men who have lower-than-normal ranges of testosterone often deal with emotional distress, including depression, as well as a lack of energy or motivation and even brain fog.
Because testosterone serves different purposes at different points in a man’s life, low testosterone can have different effects on a male depending on age. For example, if there is low testosterone during puberty, a boy may not develop facial hair or experience the same level of penile or bodily growth. However, if a grown male has low testosterone, this may have a detrimental effect on his muscle mass, libido, and possibly even play a role in hair loss.
While the body naturally produces testosterone, taking some type of supplemental testosterone is relatively common among men. Testosterone may be prescribed by a doctor for either male hypogonadism (low testosterone) or for masculinizing hormone therapy. However, many men take testosterone that may not necessarily need it, such as in the case of using the steroidal hormone for performance enhancement or building muscle. Below is a closer look at why people usually take testosterone.
The most common reason men are prescribed testosterone is due to low testosterone levels. Men can have lower than normal testosterone levels for quite a few reasons, including injury to the testes, certain metabolic disorders, pituitary gland dysfunction, and even taking certain medications. However, the most common reason a man’s natural testosterone levels drop is due to age.
A natural testosterone decline starts sometime around the age of 30; most men lose about one percent per year of age throughout life. The majority of men prescribed testosterone for low levels are at least 50 years of age or older. When testosterone levels get too low, this can bring about a lot of problems for men, including low libido, fatigue, depression, and erectile dysfunction. Men with low testosterone may have sexual difficulties that interfere with fertility, but low testosterone levels may also interfere with normal sperm production.
A relatively modern reason for testosterone therapy is masculinization, or female-to-male transitioning in order to match gender identity. Masculinizing hormone therapy is preferably started during puberty to suppress secondary sexual characteristic developments, such as menstruation and growth of the breasts. However, this form of testosterone therapy may also be used later in life for transgender men.
Testosterone’s ability to support muscle growth and strength makes it a desirable thing for people looking for performance enhancement. Certain testosterone supplements are available over-the-counter that help boost natural testosterone levels. These supplements may be safe when taken responsibly, but they should be taken only as recommended by a doctor.
Unfortunately, most men do not consult with their doctors before reaching for these over-the-counter options, and not all available products are well-tested. Some, even from trusted sources, may introduce unnecessary health risks.
As a secondary problem, the illegal use of synthetic testosterone (aka “steroids”) is also a problem among men, especially those in certain athletic fields. Synthetic steroids are often sold on the black market, which means the products are not well tested and are incredibly unreliable. In one study, over 37 percent of black market steroids contained drugs not listed on the label.
While testosterone therapy can be effective for certain purposes, the treatment does not come without risks. Some of the most common side effects of testosterone therapy include:
Long-term use of testosterone comes along with even more worrisome risks. For example, men on long-term testosterone replacement therapy may have a higher risk of heart problems. Likewise, the treatment may stimulate prostate cancer cell growth. Nevertheless, both risks can be carefully monitored as long as the patient is consistent with seeing their doctor during treatment and receives adequate periodic testing.
Naturally existing testosterone is no doubt important when it comes to a man’s levels of fertility. This primary sex hormone plays a role in everything from being interested in sex to producing enough healthy sperm to encourage fertilization during sex. However, taking testosterone may not actually mean a man is more fertile. The opposite may actually be true.
When you take testosterone, whether it’s a prescription replacement therapy due to low testosterone or a booster for performance enhancement, this changes how the body makes its own testosterone. According to Dr. Puneet Masson at Penn Medicine:
“If a man is taking any extra testosterone, it can basically shut off his body’s ability to make its own testosterone—and the body’s ability to make its own sperm.”
Testosterone therapy is already known to decrease sperm production, but if a man is getting too much testosterone, this may actually create an even bigger issue with infertility. This could generate a problem among men who take over-the-counter testosterone boosters who may not have low testosterone at all. If the supplement pushes levels too high, the body may actually not produce quality sperm.
Another reason taking testosterone and fertility may be an issue is that treatment may interfere with follicle-stimulating hormone (FSH) levels. This hormone is necessary for the male body to produce sperm. In fact, testosterone has been examined for its potential to be used as a male contraceptive for this very purpose.
If you intend to have children and plan to take testosterone for any reason, it is important to discuss the effects of treatment on fertility with your doctor. Many doctors will recommend putting off testosterone replacement therapy until after you have children. If you are already on testosterone replacement therapy or taking an over-the-counter supplement, the doctor may recommend discontinuing treatment. Of course, it is never recommended to abruptly stop doctor-prescribed treatment with testosterone without first talking to your doctor.
Keep in mind, it can take several months before sperm production rebounds, but this can also depend on the duration of treatment. Older men or men who have been taking testosterone for long periods of time may not achieve sperm quality recovery after treatment has stopped. It is actually not uncommon for men who want to have children and need testosterone replacement therapy to have their sperm preserved before starting treatment.
In finality, there is a major link between taking testosterone and fertility, even if you are only taking testosterone supplements that are easily accessible over the counter. If you intend to have biological children, it is critical that you consider how taking testosterone could interfere with those goals as a man before starting treatment, supplements, or self-medicating for performance enhancement reasons.
While taking testosterone may not mean you become completely infertile, this is not an impossibility, especially with long-term use. Be sure to talk to your doctor about fertility before starting treatment with any type of testosterone therapy.