Written by David Nazarian, MD — Board Certified in Internal Medicine
I increasingly see younger men who come to my office concerned about a low testosterone result. Some have fatigue, lower libido, reduced stamina, changes in mood, or difficulty building muscle. Others have seen a laboratory result and assume the next step is testosterone replacement therapy.
In a younger man, I do not automatically make that recommendation. A low testosterone result is the beginning of an evaluation, not the end of one.
Why I am cautious about starting TRT in younger men
Testosterone production is regulated through the hypothalamic-pituitary-gonadal axis. When testosterone is supplied from outside the body, that feedback system can suppress LH and FSH signaling, reduce the testes’ own testosterone production, and suppress sperm production. That becomes particularly important for a younger man who wants to preserve fertility.
Before discussing long-term testosterone replacement, I want to understand why his testosterone is low, whether the result has been appropriately confirmed, what symptoms he actually has, and what his reproductive goals are.
What I look for before considering treatment
I look at the entire clinical picture. Poor sleep, obesity and metabolic dysfunction, significant stress, certain medications, alcohol or substance use, sleep apnea, inadequate nutrition, and other medical conditions can influence testosterone levels or create symptoms that resemble testosterone deficiency.
That is why lifestyle is not an afterthought. Improving sleep, nutrition, exercise, body composition, and stress can be meaningful parts of the treatment plan for some younger men. When there is an underlying medical cause, that condition should be addressed rather than simply treating the laboratory number.
What about hCG?
In selected younger men, particularly when maintaining testicular function or fertility is important, I may consider alternatives to simply replacing testosterone. One option in appropriate patients is human chorionic gonadotropin, or hCG.
hCG acts similarly to LH at the testicular level and can stimulate Leydig cells to produce testosterone. It is important to understand that hCG is not simply another form of testosterone, and it does not mean every younger man with a low level should receive it. The decision depends on symptoms, laboratory findings, fertility goals, medical history, and the cause of the testosterone deficiency.
Testosterone naturally changes with age—but age alone is not a diagnosis
Testosterone levels tend to be higher in younger adulthood and can decline with age. But I do not recommend treatment based on age alone, and I do not believe the goal should be to push every man’s testosterone to a particular number.
For appropriately selected men with confirmed testosterone deficiency and compatible symptoms, testosterone therapy can be impactful. In my practice, patients may report improvements in energy, stamina, sexual function, motivation, body composition, and overall sense of well-being. Some men also report improvement in mood, but mood symptoms should not automatically be attributed to testosterone deficiency and may require separate evaluation.
I treat the patient, not just the testosterone number
This is one of the most important points I discuss with patients. Testosterone therapy is not simply about optimizing a laboratory result. I consider symptoms, repeat testing when appropriate, overall health, fertility goals, potential risks, and what the patient wants to accomplish.
For a 28-year-old man who wants children, my thinking may be very different from my approach to a symptomatic man in his 40s or 50s with repeatedly low testosterone. Individualization matters.
Related testosterone resources
Learn more about our low testosterone evaluation and testosterone replacement therapy approach. Men concerned about fertility can also read our educational discussion of low testosterone, fertility, TRT and clomiphene.
Medical note: This article is educational and does not replace an individualized medical evaluation. Testosterone therapy and fertility-directed treatment have potential benefits, risks, contraindications, and monitoring requirements.
