Male Hypogonadism: Open Controversies in the Field

Controversy 1: Is There One Correct Testosterone Threshold?

There is no threshold that can diagnose every patient without context. The American Urological Association guideline uses total testosterone below 300 ng/dL as a reasonable cutoff supporting the diagnosis 1. The Endocrine Society guideline recommends distinguishing hypogonadal from normal testosterone using accurate assays and rigorously derived reference ranges, then confirming an initially low result with repeat morning fasting testing 2.

Those positions are closer than they first appear. Both require symptoms and repeat testing; neither supports prescribing from one isolated value. Differences emerge near the lower limit, where assay reference ranges, sex hormone-binding globulin (SHBG), age, obesity, medications, sleep, acute illness, and sampling conditions can shift the result or its meaning.

The Endocrine Society's July 2026 statement describes a common clinical threshold near 300 ng/dL but stresses accurate diagnosis and at least two early-morning fasting tests 3. The controversy is therefore not whether 299 and 301 ng/dL are biologically different. It is how to combine a continuous laboratory measure with symptoms, cause, and measurement uncertainty.

Controversy 2: How Reliable Is the Laboratory Result?

Testosterone varies within the same person. Food intake, time of day, sleep disruption, acute illness, and some medications can affect a measurement. Repeat morning testing reduces, but does not eliminate, misclassification.

Assay standardization is another concern. The CDC Hormone Standardization Program evaluates testosterone and estradiol methods for bias and imprecision and publishes a current list of certified assays 4. Certification does not make clinical interpretation automatic, but it reduces the chance that the same sample is categorized differently because of avoidable calibration problems.

When Free Testosterone Matters

Most circulating testosterone is protein-bound. When SHBG is unusually high or low, total testosterone may not reflect the free fraction in the expected way. The Endocrine Society recommends obtaining free testosterone by equilibrium dialysis or an accurate calculation when total testosterone is near the lower limit or a condition alters SHBG 2.

“Direct free testosterone” immunoassays, calculated values, and equilibrium dialysis are not interchangeable. A calculated result inherits error from total testosterone, SHBG, albumin, and the chosen equation. This is one reason an ambiguous laboratory profile belongs in clinical interpretation rather than an online dose calculator.

Controversy 3: Is Obesity-Associated Low Testosterone a Disease or a Reversible State?

Obesity can lower SHBG and total testosterone and can suppress the hypothalamic-pituitary-gonadal axis. Sleep apnea, type 2 diabetes, chronic illness, and medicines may coexist. Some men also have a separate pituitary or testicular disorder; weight should not be used to dismiss a genuine diagnosis.

The 2026 Endocrine Society statement says weight loss is typically first-line when appropriately diagnosed hypogonadism is associated with overweight or obesity and no other cause is identified 3. The unresolved issue is which patients will normalize testosterone and symptoms with weight-focused care, which need concurrent evaluation, and whether testosterone adds net benefit beyond treating the underlying drivers.

Finding a Cause Changes the Treatment Question

Low testosterone is a laboratory finding before it is a diagnosis. Elevated LH and FSH with low testosterone points toward primary testicular dysfunction; low or inappropriately normal gonadotropins can point toward hypothalamic or pituitary suppression. Prolactin, iron overload, pituitary symptoms, testicular history, opioid or glucocorticoid exposure, severe systemic illness, and sleep-disordered breathing can change the workup.

This distinction is not academic. Testosterone may replace a deficient hormone but does not treat a pituitary mass, reverse medication suppression, or restore sperm production. In secondary hypogonadism, fertility-focused therapy follows a different logic from replacement. An unexplained pattern should not be converted directly into a retail TRT regimen.

Controversy 4: What Did TRAVERSE Settle About the Heart?

TRAVERSE enrolled 5,246 men ages 45 to 80 with symptoms, two fasting testosterone concentrations below 300 ng/dL, and preexisting cardiovascular disease or high cardiovascular risk. A primary cardiovascular event occurred in 7.0% of the testosterone group and 7.3% of the placebo group; testosterone was noninferior for the prespecified major-cardiovascular-event endpoint 5.

This substantially improved the evidence base, but “noninferior for the primary endpoint” is narrower than “TRT is risk-free.” Higher incidences of atrial fibrillation, acute kidney injury, and pulmonary embolism were observed with testosterone. Trial duration, product used, adherence, enrolled population, and event definitions limit how far the result can be generalized.

FDA responded in 2025 by removing class-wide boxed-warning language about increased adverse cardiovascular outcomes, adding TRAVERSE results, retaining limitation-of-use language for age-related hypogonadism, and requiring blood-pressure warnings after ambulatory blood-pressure studies showed a class-wide increase 6. Blood pressure, hematocrit, symptoms, and individual cardiovascular history remain clinically relevant.

Controversy 5: Which Older Men Benefit?

Symptoms often attributed to “low T,” including fatigue, reduced libido, depressed mood, sleep problems, and loss of strength, also become more common with age for many other reasons. Treating age alone risks medicalizing nonspecific symptoms; refusing evaluation because of age can miss genuine pituitary or testicular disease.

The Testosterone Trials enrolled 790 men age 65 or older with low testosterone. Testosterone produced modest benefits in some sexual-function outcomes, while results across vitality, physical function, and cognition were not uniformly positive 7. The trial helps define realistic expectations but does not identify a universal responder profile or establish decades-long safety.

The current diagnostic approach is the same at any age: establish symptoms, repeat accurate measurements, and look for causes. The benefit-risk discussion may differ because baseline prostate, cardiovascular, sleep-apnea, and fertility priorities differ.

Controversy 6: Fertility Suppression and Recovery

Exogenous testosterone applies negative feedback to the hypothalamic-pituitary-gonadal axis, lowering LH and FSH and reducing intratesticular testosterone. Sperm concentration can fall markedly or reach azoospermia. For this reason, major guidelines advise against testosterone therapy when fertility is planned in the near term 2.

Recovery after stopping is variable. A clinical review notes that data describing unassisted recovery after long-term TRT are limited and are partly extrapolated from male-contraceptive studies 8. Baseline testicular function, age, duration, dose, and other androgen exposure can affect recovery. Claims that everyone recovers by a fixed month, or that everyone needs the same hCG or SERM protocol, go beyond the evidence.

The practical answer is to ask about reproductive goals before the first prescription. Men currently using testosterone who want fertility need individualized reproductive-urology or endocrinology assessment rather than a self-directed “post-cycle” schedule.

Controversy 7: Prostate Safety and Monitoring

Shorter-term trial and observational data have not established that physiologic testosterone replacement causes new prostate cancer, but absence of a clear signal is not proof of lifetime neutrality. Prostate cancers often evolve over longer periods than treatment trials.

The 2018 Endocrine Society guideline recommends against initiating therapy in men with prostate cancer or certain concerning prostate findings without further urologic evaluation 2. Screening and monitoring decisions depend on age, baseline risk, patient preferences, prior results, and current product labeling. The open question is especially important for men with a history of treated localized prostate cancer, where evidence and recommendations continue to evolve.

Controversy 8: How Should New Safety Signals Be Communicated?

TRAVERSE is often reduced to a slogan about heart attacks. The complete result is more useful. Its primary MACE endpoint was reassuring, while atrial fibrillation, acute kidney injury, and pulmonary embolism occurred more often with testosterone 5. The 2026 Endocrine Society statement also highlights a higher fracture incidence and calls for longer-term research 3.

A secondary signal does not automatically prove causation, and it should not be erased because the primary endpoint passed. Clinicians need to explain the event, absolute frequency where established, uncertainty, and relevance to the individual. Marketing language that says “FDA cleared the heart risk” is as incomplete as older blanket warnings that treatment inevitably causes a heart attack.

Controversy 9: What Outcomes Should Count as Success?

A testosterone number moving into a laboratory reference range is not by itself a patient-centered outcome. Meaningful outcomes can include improvement in the symptom that prompted evaluation, correction of anemia in an appropriate patient, sexual function, bone health, adverse effects, blood pressure, hematocrit, and fertility goals.

Nonspecific promises such as “more energy,” “anti-aging,” “metabolic reset,” or guaranteed body-composition change are hard to separate from placebo effects, concurrent weight change, sleep treatment, exercise, and regression to the mean. Trials show average effects; individuals may benefit, have no meaningful response, or experience harms.

Treatment Targets Are Not One Universal Number

Guidelines generally aim for testosterone in a physiologic range, but the timing of measurement depends on the product. A gel level, a trough before an injection, and a level measured soon after an injection do not mean the same thing. Symptoms, hematocrit, blood pressure, adverse effects, and the reason for treatment must be interpreted alongside the number.

Chasing a high-normal concentration is not evidence-based if the original symptom has not improved. Conversely, a patient with a meaningful response still needs safety monitoring. A pre-specified reassessment point helps separate ongoing benefit from indefinite treatment maintained only because the laboratory value changed.

An Evidence-Based Diagnostic Framework

1. Define the symptom or sign. Low libido, reduced spontaneous erections, infertility, unexplained anemia, low bone density, testicular changes, or pituitary features carry different diagnostic weight from fatigue alone.
2. Obtain repeat reliable testing. Use early-morning fasting samples and avoid diagnosing during acute illness when possible.
3. Interpret SHBG and free testosterone when indicated. Do not assume a direct assay and a validated calculation are equivalent.
4. Identify the level and cause. LH and FSH help distinguish primary from secondary hypogonadism; history and targeted testing assess pituitary, medication, sleep, systemic-disease, and weight-related contributors.
5. Discuss fertility before treatment. Testosterone replacement is not fertility treatment.
6. Set a measurable goal and monitoring plan. Define what improvement would justify continuation and how blood pressure, hematocrit, prostate risk, symptoms, and product-specific effects will be followed.

What Remains Genuinely Unknown

The largest gaps are long-term. Current trials do not tell us the lifetime prostate and cardiovascular effects of starting therapy in midlife, the best strategy for obesity-associated low testosterone, the optimal individualized target concentration, or which men with borderline levels and nonspecific symptoms will experience net benefit. Better standardized testing narrows diagnostic noise, but it does not eliminate the need for judgment.

Research also underrepresents some clinically important groups. Men actively pursuing fertility, men with recent cardiovascular events, many prostate-cancer survivors, and patients with complex pituitary disease are not fully represented by the major efficacy and safety trials. Extrapolation should be identified as extrapolation, not hidden behind a broad claim that “studies show TRT is safe.”

Future guidance will also have to reconcile changing regulation with trial uncertainty. FDA's 2025 label action addressed cardiovascular-warning language and blood pressure, while the 2026 Endocrine Society statement called for longer follow-up and more standardized diagnosis 36. Neither update makes symptoms, repeat testing, cause, or patient goals optional.

The strongest page on this topic should preserve the disagreement instead of manufacturing a winner. Thresholds guide decisions but do not replace symptoms; trials reduce uncertainty but do not create lifetime evidence; and a treatment that is appropriate for established testicular or pituitary disease may not have the same benefit-risk balance when low testosterone is associated with obesity, aging, medication use, or an unclear cause.