Men’s testicles hang lower with age primarily because the scrotal skin loses elasticity and the muscles responsible for pulling the scrotum tight against the body grow weaker over time. These changes are gradual, driven by the same connective-tissue breakdown that causes skin everywhere on the body to sag, combined with hormonal shifts and reduced muscle tone specific to the scrotum. The process is universal and completely normal, though the degree of sagging varies from person to person. Understanding why it happens requires looking at the scrotum not as a passive sack but as a surprisingly active organ with its own muscles, blood supply, and temperature-regulation system, all of which change as the decades pass.
Skin and Connective Tissue Lose Their Snap
Scrotal skin is among the thinnest on the human body, and it contains the same structural proteins, collagen and elastin, that give skin elsewhere its firmness and recoil. Starting in roughly the mid-thirties, collagen production declines across the entire body by about one percent per year. Elastin fibers, which allow tissue to stretch and snap back, also degrade and are barely replaced in adulthood. The scrotum is especially vulnerable to these changes because it is already designed to be loose and flexible. Where facial skin might take decades to show visible sagging, the scrotum has far less structural scaffolding to begin with, so the same percentage of collagen loss translates into more noticeable drooping. Clinically, this progressive looseness is described as scrotal laxity, and it is one of the most recognized age-related morphological changes in the male genitalia.1PubMed Central. Scrotal Rejuvenation
Gravity is a constant, low-grade contributor. Unlike the skin on your face or arms, which rests against muscle and bone, scrotal skin hangs freely. The weight of the testicles, which range from about 15 to 25 grams each in a healthy adult, applies a continuous downward pull. Over years, weakened connective tissue yields to that pull more readily. Heat, friction from clothing, and moisture can further accelerate the breakdown of the skin’s elastic fibers in this region, compounding the effects of biological aging.
The Dartos and Cremaster Muscles Lose Tone
The scrotum is not just skin. Embedded within its wall is a thin sheet of smooth muscle called the dartos muscle, which is responsible for the wrinkling and tightening you see when the scrotum contracts in cold temperatures. Separately, the cremaster muscle, a skeletal muscle running along the spermatic cord, pulls each testicle individually upward toward the body. Together, these muscles give the scrotum its ability to ride high and tight against the body or hang low and relaxed depending on conditions.
Both muscles weaken with age. Smooth muscle throughout the body loses contractile strength over time, and the dartos is no exception. Research on dartos muscle physiology has shown that its ability to maintain resting tension in cold conditions depends on a temperature-sensitive receptor called TRPM8, and that the expression of this receptor requires a functioning androgen receptor.2PubMed Central. Temperature-dependent contractility of rat tunica dartos muscle: Contribution of cold, menthol-sensitive TRPM8 Since testosterone levels decline gradually with age, the downstream signaling that keeps the dartos muscle responsive to temperature cues also diminishes. The result is a scrotum that spends more of its time in a relaxed, elongated state simply because the muscle that would otherwise pull it taut is less active.
The cremaster muscle follows a similar trajectory. Skeletal muscle mass and reflexive contractility decline with age across the entire body, and the cremaster is a small muscle to begin with. The cremasteric reflex, the involuntary contraction triggered by touching the inner thigh, becomes harder to elicit in older men, which is a straightforward clinical sign that the muscle is less responsive.
How Thermoregulation Fits In
The scrotum’s ability to move is not a cosmetic feature. It exists to regulate the temperature of the testicles, which produce sperm most effectively at a temperature a few degrees below core body temperature. When conditions are cold, the dartos and cremaster muscles contract to pull the testes closer to the body for warmth. When conditions are warm, the muscles relax and the scrotum drops to increase the surface area available for heat dissipation.
This system is remarkably active in younger men. A 2025 study measuring scrotal temperature during running found that scrotal skin temperature behaved in the opposite direction from the rest of the body immediately after exercise began: while other body surfaces initially cooled, scrotal temperature rose. The researchers attributed this partly to contraction of the cremaster and dartos muscles driven by sympathetic nervous system activation during exercise.3PubMed Central. Scrotal temperature change during running in naked humans This kind of rapid, reflexive response to exercise and ambient temperature is what keeps the scrotum dynamic throughout the day in a younger man.
As the muscles weaken and skin loses elasticity, the system becomes sluggish. The scrotum still responds to temperature, but the excursion between its tightest and most relaxed states narrows. In practical terms, an older man’s scrotum tends to settle into a lower resting position and does not retract as dramatically in response to cold or physical activity. The thermoregulatory function still works, just with less range.
Falling Testosterone Compounds the Problem
Testosterone production declines by roughly one to two percent per year after age 30 in most men. This matters for scrotal sagging through at least two pathways. First, as mentioned, the dartos muscle’s ability to maintain cold-induced tension depends on androgen receptor signaling. Less testosterone means less receptor activation, which means a less responsive dartos muscle.2PubMed Central. Temperature-dependent contractility of rat tunica dartos muscle: Contribution of cold, menthol-sensitive TRPM8
Second, testosterone has a general trophic effect on muscle tissue, meaning it supports muscle maintenance and growth. The age-related decline in testosterone contributes to the loss of muscle mass and strength throughout the body, a process sometimes called sarcopenia. The cremaster and dartos muscles, though small, are subject to the same forces. In aging studies on rats, the Leydig cells that produce testosterone were found to shrink substantially, with average cell volume dropping by more than half over the animals’ lifespan.4PubMed. Ultrastructure and morphometry of testicular Leydig cells and the interstitial components correlated with testosterone in aging rats While rat physiology does not map perfectly to humans, the directional finding is consistent with what clinicians observe: lower testosterone over time, less muscular support for the scrotum, more sagging.
Varicoceles and Vascular Changes
Beyond skin, muscle, and hormones, the blood vessels within and around the scrotum change with age in ways that can contribute to a heavier, lower-hanging appearance. Varicoceles, which are dilated veins in the spermatic cord, become markedly more common in older men. A study of men in an elderly population found varicoceles present in about 42 percent of subjects, a prevalence considerably higher than what is typically seen in younger men.5PubMed. Prevalence and effect of varicoceles in an elderly population The same study found that men with bilateral varicoceles had significantly smaller and softer testes compared to those without varicoceles, suggesting that the vascular changes may also affect the testicles themselves.
Varicoceles add a feeling of fullness and weight to the scrotum, and higher-grade varicoceles were more strongly associated with softer testes.5PubMed. Prevalence and effect of varicoceles in an elderly population Most varicoceles are painless and go unnoticed, but in some men they cause a dull aching sensation, especially after standing for long periods. Whether the rising prevalence in older men reflects genuine new development of varicoceles or just the accumulation and worsening of existing ones remains an open question in urology. Either way, they are part of the constellation of changes that make the scrotum hang differently over time.
Hydroceles, pockets of fluid that accumulate around a testicle, also become more common with age and can produce visible swelling. While a hydrocele is a distinct condition from ordinary sagging, a small, asymptomatic hydrocele can make one side of the scrotum noticeably larger and lower, blending in with what a man might perceive simply as “more sagging.”
Does Extra Sagging Affect Fertility or Sexual Function?
Men sometimes worry that increased scrotal length indicates something is going wrong with their reproductive system. The reassuring answer is that moderate sagging by itself does not appear to harm sperm production. One study that artificially raised scrotal temperature by about one degree Celsius using athletic supports found no significant effect on sperm concentration, motility, morphology, or ability to fertilize eggs.6Fertility and Sterility. Effect of increased scrotal temperature on sperm production in normal men A scrotum that hangs lower is simply dissipating heat more effectively, which, if anything, supports spermatogenesis rather than impairing it.
That said, the conditions that sometimes accompany age-related scrotal changes can matter. Large varicoceles, for example, are associated with reduced testicular volume and softer testicular tissue, both of which are markers of impaired function.5PubMed. Prevalence and effect of varicoceles in an elderly population And while a modest temperature increase from a low-hanging scrotum is benign, prolonged exposure to much higher heat, from laptops on the lap, extended hot tub use, or occupational heat exposure, can temporarily reduce sperm quality. The distinction is between normal gravitational sagging, which is harmless, and pathological conditions or extreme heat exposure, which deserve clinical attention.
For sexual function specifically, sagging itself is not a mechanical obstacle. The scrotum’s position has no direct bearing on erection quality or ejaculatory function. However, the psychological dimension is real, which brings up another side of the issue.
How Genital Self-Image Affects Well-Being
Research on men’s genital self-image has found that dissatisfaction with the appearance of the genitals correlates with higher rates of depression and anxiety, and that these psychological effects spill over into sexual performance.7PubMed. The impact of male genital self-image on depression, anxiety and sexual functions Scrotal sagging is one of the appearance changes that some men find distressing, especially if it develops faster than expected or becomes pronounced enough to cause physical discomfort, such as sitting on the scrotum or chafing during exercise.
This is an area where medicine has historically been dismissive. Changes in scrotal appearance have not traditionally been treated as medically meaningful, partly because they carry no direct health risk and partly because men are less likely to raise cosmetic genital concerns with their doctors. But discomfort, whether physical or psychological, is a valid reason to seek advice. Supportive underwear with a pouch design, for instance, is a simple and completely adequate solution for most men who experience physical inconvenience from a low-hanging scrotum. For those whose distress goes beyond the physical, speaking with a healthcare provider about genital self-image concerns is not frivolous; the link between negative self-perception and downstream effects on mood and sexual satisfaction is well documented.
When Men Seek Treatment
Scrotal laxity is generally treated as a cosmetic concern rather than a medical one, but interventions do exist. Surgical scrotoplasty, which removes excess scrotal skin, is the most established approach for significant laxity.1PubMed Central. Scrotal Rejuvenation The procedure is relatively straightforward and has been performed for decades, though it is far more common in cases of pathological enlargement, like scrotal lymphedema, than for age-related drooping alone. Absorbable suspension sutures have been proposed as a less invasive alternative to achieve a scrotal lift, though the evidence base for this technique is thin and mostly hypothetical at this point.
Botulinum toxin injections into the dartos muscle have been discussed as a treatment for scrotal wrinkling, which sounds counterintuitive since the goal for sagging would be more muscle tone, not less.1PubMed Central. Scrotal Rejuvenation The logic behind it is specific to the appearance of fine wrinkles rather than low-hanging laxity. In practice, men bothered by sagging are more commonly advised to try supportive underwear and manage expectations, since some degree of increased scrotal length is a normal part of aging that no underwear or procedure will permanently reverse.
For men with large varicoceles contributing to scrotal heaviness or discomfort, varicocelectomy, a surgical procedure to ligate the dilated veins, is a well-established option. This does not address skin laxity, but it can reduce the feeling of fullness and the aching that sometimes accompanies prominent varicoceles.
Why Testicles Hang Outside the Body in the First Place
The fact that testicles are external at all is unusual among organs. Most mammals have descended testes, but the degree of descent varies enormously across species. Elephants, for instance, retain their testes internally, while many rodents have testes that move freely between the abdomen and scrotum depending on season. The dominant explanation for external testes centers on temperature: sperm production in most mammalian species requires temperatures a few degrees below core body heat, and the scrotum provides that cooler environment.
But the full story is more nuanced. One evolutionary analysis argues that testicular location is not purely a temperature-management solution but rather the result of coordinated cellular signaling that sought an optimal balance point once mammals became endothermic, meaning they maintained constant high body temperatures internally.8PubMed Central. Reappraising the exteriorization of the mammalian testes through evolutionary physiology Under this view, the testes migrated outward over evolutionary time in response to the stresses that constant high internal temperatures placed on reproductive cells, eventually settling at a location that balanced thermal needs with other physiological requirements.
This evolutionary backdrop matters for understanding age-related sagging because it highlights that the scrotum was never designed for structural rigidity. It was designed for dynamic movement, responding to temperature cues by retracting or relaxing constantly. The architecture is built for flexibility, not firmness. When the muscles and skin that enable that flexibility degrade with age, the scrotum has nothing to fall back on, literally. There is no bony scaffold, no dense fascia, no cartilage. The design that makes the scrotum so good at thermoregulation in youth is exactly what makes it vulnerable to gravity in old age.
Individual Variation and What Speeds Things Up
Not all men experience the same degree of scrotal sagging at the same age. Genetics play a role in baseline skin elasticity, connective tissue density, and the rate of collagen loss. Body weight matters too. Men who carry more abdominal fat tend to have higher groin temperatures, which keeps the scrotum in a more relaxed state for longer periods, potentially accelerating stretching over time. Conversely, men who maintain lower body fat and higher testosterone levels through physical activity may preserve some scrotal muscle tone longer.
Occupational and lifestyle factors contribute as well. Prolonged sitting, especially on soft or heated surfaces, keeps the scrotum in a fully relaxed, gravity-dependent position for hours at a time. Men who work in high-heat environments, such as commercial kitchens, foundries, or bakeries, subject their scrotal skin to conditions that break down elastin faster. Tight clothing that compresses the scrotum against the body might paradoxically delay some sagging by limiting gravitational pull, though the trade-off is higher scrotal temperature.
Smoking accelerates skin aging throughout the body by damaging collagen and reducing blood flow to the skin. The scrotum is no exception. Chronic smokers tend to show signs of premature skin aging, and while no study has isolated scrotal skin specifically, the mechanism is the same everywhere: reduced oxygen delivery to dermal cells, increased oxidative stress, and faster breakdown of structural proteins. If you are looking for a modifiable risk factor in scrotal sagging, smoking cessation is probably the single most impactful lifestyle change, not because it reverses existing damage, but because it slows the ongoing degradation of the connective tissue that is doing what little structural work the scrotum has left.