What Causes Testosterone to Be High in Men and Women

Testosterone can be elevated by dozens of different mechanisms, and the most likely culprit depends heavily on whether you are male or female. In women, the single most common driver is polycystic ovary syndrome, which accounts for the vast majority of non-tumor hyperandrogenism cases. In men, genuinely elevated testosterone from internal causes is rarer and usually points to a testicular or adrenal tumor, though exogenous testosterone use has become a widespread source. Beyond these headline causes, obesity, insulin resistance, genetic enzyme defects, certain medications, pregnancy, and even shared towels can push testosterone above normal range.

Why the Causes Split Along Sex Lines

Before puberty, boys and girls circulate roughly similar amounts of testosterone. Once the testes ramp up production during male puberty, they produce about 30 times more testosterone than they did before, and adult men carry circulating testosterone levels roughly 15-fold higher than women at any age.¹ That enormous baseline gap means “high testosterone” can mean very different things. A woman whose total testosterone doubles from a normal level of around 40 ng/dL to 80 ng/dL may experience obvious physical changes like unwanted facial hair, acne, and menstrual disruption. A man whose testosterone rises from 500 to 700 ng/dL might notice nothing at all, or might feel slightly more energetic. The clinical thresholds, the symptoms, and the likely diagnoses all diverge.

Polycystic Ovary Syndrome

PCOS is, by a wide margin, the most common explanation for elevated testosterone in women. Once androgen-producing tumors have been ruled out, PCOS is the diagnosis clinicians reach for first.² The condition affects an estimated 6 to 12 percent of women of reproductive age, depending on which diagnostic criteria are used, making it one of the most prevalent endocrine disorders worldwide.

The androgen excess in PCOS is primarily ovarian in origin. Studies comparing women with PCOS to controls have found that both total and free testosterone are substantially higher in the PCOS group. In one study, total testosterone averaged about 93 ng/dL in the PCOS group versus roughly 44 ng/dL in controls, and androstenedione (another androgen) was similarly elevated.³ Interestingly, not every androgen rises equally. DHEA, which comes mainly from the adrenal glands, was not significantly elevated in these women, pointing to the ovaries as the primary source.

A separate line of research has shown that women with PCOS excrete about 1.9 times more testosterone and androstenedione metabolites in their urine compared to women without the syndrome, even after adjusting for body weight.⁴ The problem is not just that the ovaries produce too much testosterone; the whole steroid processing system runs differently.

The Insulin Connection

Insulin resistance sits right at the intersection of PCOS and obesity, and it independently drives androgen production in women. The ovaries and adrenal glands remain sensitive to insulin even when other tissues have become resistant to it, so when insulin levels climb to compensate for that resistance, those glands respond by making more androgens. Among women with severe insulin resistance syndromes, the elevated insulin promotes ovarian androgen synthesis on its own, regardless of what the pituitary hormones are doing.⁵ This is one reason why metformin and other insulin-sensitizing drugs can lower testosterone in women with PCOS even though those drugs have nothing to do with sex hormones directly.

The Obesity Paradox

Body weight affects testosterone in opposite directions depending on your sex. Obese women tend to develop higher androgen levels, while obese men tend to see testosterone fall. One study found that testosterone in obese women was significantly higher than in normal-weight controls (about 2.0 vs. 1.3 ng/L), while in obese men it was significantly lower (about 18.6 vs. 23.3 ng/L).⁶ The abdominal pattern of fat distribution seems especially linked to androgen excess in women.⁷

Part of this picture involves sex hormone-binding globulin (SHBG), a protein that carries testosterone through the blood and keeps it inactive. Obesity lowers SHBG levels. In women, this liberates more free testosterone from its protein carrier, increasing the hormone’s biological activity even when total testosterone does not change dramatically. In obese men, the math works out differently: lower SHBG means lower total testosterone readings, and the free testosterone drops too.⁸ So for men wondering why their testosterone is high, excess body fat is almost never the answer. For women, it frequently is.

Congenital Adrenal Hyperplasia

Not all elevated testosterone in women comes from the ovaries. The adrenal glands sit on top of the kidneys and produce their own androgens, and a genetic condition called nonclassic congenital adrenal hyperplasia (NCAH) can cause them to overproduce. NCAH is caused by a partial defect in the 21-hydroxylase enzyme, which leads to normal cortisol production but excessive adrenal androgens.⁹ It is often first noticed when a young woman develops unwanted facial hair and irregular cycles, and the diagnosis typically comes from elevated 17-hydroxyprogesterone levels confirmed by a stimulation test.¹⁰

NCAH is surprisingly common in certain populations. The condition can overlap clinically with PCOS to such an extent that clinicians sometimes mistake one for the other, which matters because the treatment approach differs. NCAH typically responds to low-dose glucocorticoids that suppress adrenal androgen output, while PCOS management usually focuses on oral contraceptives or insulin sensitizers.

Androgen-Producing Tumors

Tumors that secrete androgens are rare but represent the cause that clinicians most urgently want to rule out, because the testosterone levels they produce can be extreme and the tumors can be malignant. Among all women presenting with hyperandrogenism symptoms, androgen-producing tumors account for roughly 0.2% of cases.¹¹ These tumors can arise from either the ovary or the adrenal gland.

Red flags that point toward a tumor rather than PCOS or NCAH include rapid onset of virilizing symptoms (deepening voice, male-pattern hair loss, clitoral enlargement), extremely high testosterone levels, and onset after menopause. In postmenopausal women, new-onset hirsutism with elevated testosterone or DHEA-S should prompt imaging of both the adrenals and ovaries.¹²

In men, testosterone-producing tumors are also uncommon but do occur. Leydig cell tumors of the testis can secrete enough testosterone to suppress the brain’s signals to the testes, paradoxically shutting down sperm production even while androgen levels soar. One case study documented a man with a Leydig cell tumor whose testosterone was so high it suppressed both LH and FSH, causing complete azoospermia (no sperm in the ejaculate).¹³ The clinical picture can be confusing, because high testosterone does not always produce obvious outward symptoms in men who are already virilized. Weight gain, mood changes, and gynecomastia (breast tissue growth from conversion of excess testosterone to estrogen) may be the presenting complaints.¹⁴

Testosterone During Pregnancy

Pregnancy is a lesser-known but real cause of high testosterone in women. Testosterone normally rises throughout pregnancy as the placenta and ovaries increase steroid production. In some pregnancies, this process goes further than expected. A condition called hyperreactio luteinalis involves exaggerated ovarian enlargement with markedly elevated testosterone, androstenedione, and dihydrotestosterone. In reported cases, the mother developed virilizing symptoms during the third trimester, but androgen levels gradually returned to normal after delivery.¹⁵ Pregnancy luteomas, benign growths of ovarian tissue, can produce a similar picture.¹⁶

These conditions are self-limiting, resolving after delivery. The clinical concern during pregnancy is not for the mother but for the fetus: very high maternal androgens can theoretically masculinize a female fetus, though placental enzymes normally convert most testosterone to estrogen before it reaches fetal circulation.

Exercise, Sleep, and Situational Spikes

Lifestyle factors can temporarily push testosterone up, though the magnitude is generally smaller and more fleeting than the endocrine disorders described above. Exercise is the factor that gets the most attention. Heavy resistance training tends to produce an acute rise in testosterone in men, although the size and duration of the spike vary considerably based on the type of exercise, rest periods, age, fitness level, and when blood is drawn.¹⁷ In women, the evidence is mixed, with some studies showing small increases after resistance exercise and others showing none.¹⁸ The acute post-workout bump is real but transient, and there is little evidence it produces chronically elevated levels on its own.

Sleep has a well-documented relationship with testosterone. In men, testosterone peaks during sleep and bottoms out in the late afternoon. This sleep-dependent rise requires at least about three hours of sleep with normal architecture.¹⁹ The flip side of this is that chronic sleep deprivation tends to lower testosterone rather than raise it. So sleep is more relevant as an explanation for low testosterone than for high testosterone. If a blood draw catches you early in the morning after a full night’s sleep, the reading may be higher than one taken at 4 p.m., simply because of this normal daily rhythm.

Even social situations can produce measurable testosterone fluctuations. Competitions, status challenges, and being evaluated by others tend to produce coordinated rises in both testosterone and cortisol.²⁰ The pattern is not as simple as “winners get a testosterone boost,” though. Research on competitive outcomes found that decisiveness of the win mattered: among people with high baseline cortisol, narrow wins actually reduced testosterone compared to clear wins.²¹ These fluctuations are biologically interesting but small and short-lived, so they would not explain a consistently elevated lab result.

Accidental Exposure to Topical Testosterone

A growing and underappreciated cause of elevated testosterone in women and children is secondhand contact with testosterone gels or creams prescribed to a male partner or family member. A published case documented a postmenopausal woman who developed virilization from sharing a washcloth with her husband, who used a topical testosterone product. The couple was actually aware of the potential for transfer, yet the contaminated washcloth was enough to raise her testosterone to virilizing levels.²² With millions of testosterone prescriptions filled annually, this kind of inadvertent transfer is probably more common than the published case reports suggest. Touching skin where gel was recently applied, sharing bedding, or cuddling shortly after application can all transfer meaningful amounts.

Why Measurement Matters

Before accepting that your testosterone is genuinely high, it is worth understanding that not all testosterone tests are equally accurate. The standard immunoassay used in many commercial labs can significantly undercount testosterone at low concentrations, which matters most for women. One study comparing immunoassay to the more precise mass spectrometry method found that immunoassay readings were about 20% lower and correlated poorly with mass spectrometry at concentrations below 100 ng/dL.²³ Since most women’s testosterone falls well below 100 ng/dL, this means the standard test can give unreliable results in the population where androgen excess matters most. If you are a woman with borderline results, requesting a mass spectrometry-based assay can make a real diagnostic difference.

The binding protein SHBG also complicates interpretation. Total testosterone is what most labs report, but much of that testosterone is bound to SHBG and biologically inactive. Aging, genetics, liver disease, thyroid conditions, and medications like oral contraceptives all shift SHBG levels, which in turn change how much free testosterone is available to act on tissues, without changing the total number at all.²⁴ Two people with identical total testosterone readings can have very different levels of biologically active hormone.

What Ovarian Aging Does to Androgens

A common assumption is that all sex hormones decline after menopause, but for testosterone the story is more nuanced. Research measuring testosterone directly from the ovarian vein (rather than peripheral blood) found that ovarian testosterone production actually increased with age, rising from a median of about 1.5 nmol/L in premenopausal women to 2.5 nmol/L in postmenopausal women. Ovarian stromal hyperplasia was associated with this increased secretion.²⁵ However, this local increase does not necessarily translate into higher testosterone in the bloodstream, because other ovarian androgens decline and the adrenal contribution changes. The question of whether the postmenopausal ovary is truly a significant androgen factory remains debated; one study examining the predominant stromal cells of the postmenopausal ovary concluded that they are not a major site of androgen production.²⁶ The practical upshot: if a postmenopausal woman has clearly elevated peripheral testosterone, do not assume it is just menopause. It warrants investigation.

Health Consequences of Chronically High Testosterone

Elevated testosterone is not just a lab curiosity. A large genetic study using data from hundreds of thousands of people found that the health effects of lifelong high testosterone differ strikingly between men and women. In women, genetically higher testosterone increased the risk of type 2 diabetes (by roughly 37%) and polycystic ovary syndrome (by about 51%), along with adverse effects on breast and endometrial cancer risk. In men, the same genetically driven higher testosterone actually reduced type 2 diabetes risk by about 14%, though it raised prostate cancer risk.²⁷

A complementary study looking at free testosterone specifically found that higher levels were associated with increased bone density and lower body fat (both beneficial), but also with lower HDL cholesterol, higher blood pressure, increased prostate cancer risk, androgenic hair loss, and spinal stenosis.²⁸ Some of these effects are clearly helpful while others are harmful, which is why blanket statements like “testosterone is good” or “testosterone is bad” miss the mark entirely. The effects are sex-specific, tissue-specific, and dose-specific.

Testosterone and Life-History Tradeoffs in Females

An evolutionary perspective adds a layer that clinical medicine often overlooks. Across female mammals, testosterone appears to mediate a fundamental tradeoff: females with relatively low testosterone tend toward earlier reproduction, higher offspring production, and greater attractiveness to males, while those with higher testosterone tend toward delayed reproduction but increased dominance, status, and resource acquisition.²⁹ This is not a value judgment about what is “better” but a description of how the hormone shapes behavioral and reproductive strategies. It also helps explain why some degree of variation in female testosterone levels is normal and perhaps adaptive, rather than pathological. The clinical threshold for “too high” is ultimately defined by whether the level is causing symptoms or health risks, not by an abstract ideal.