Yes, men take estrogen for several reasons, and men’s bodies actually produce it naturally. Adult males normally have estradiol (the primary form of estrogen) circulating at levels of 20 to 50 pg/mL. About 20% of that comes from the testes, while the remaining 80% is produced when testosterone gets converted into estradiol in other tissues throughout the body. This natural estrogen plays a surprisingly important role in male health, and in certain medical situations, men take additional estrogen as a prescribed treatment.
Why Men’s Bodies Need Estrogen
Estrogen isn’t just a “female hormone.” In men, it helps regulate bone density, sexual function, mood, and brain health. As estrogen levels decline with age, bone mineral density drops in parallel. Men who lack estrogen entirely due to rare genetic conditions develop unfused growth plates, meaning their bones never stop growing lengthwise, and they become abnormally tall with weakened skeletons. Estrogen is what signals bones to stop growing during puberty and what keeps them strong afterward.
In the brain, testosterone is routinely converted into estradiol, giving men relatively stable estrogen activity in brain tissue at all times. This steady supply influences serotonin function, which helps regulate mood. Higher estrogen levels have been associated with less depression in older adults of both sexes. Estrogen also plays a direct role in male sexual desire. In men with low testosterone, sexual drive was markedly higher when estradiol levels remained above a certain threshold, and studies suggest both hormones are needed together for normal libido.
Gender-Affirming Hormone Therapy
The most common reason men are prescribed estrogen today is feminizing hormone therapy for transgender women. This treatment uses estradiol in combination with medications that block testosterone to trigger the development of feminine physical characteristics and reduce gender dysphoria. The goals include improving psychological well-being, social comfort, and quality of life.
Estradiol is the preferred form because it closely resembles the hormone produced by the ovaries. It can be delivered through skin patches, implants, or tablets. Patches typically start at 100 micrograms per 24 hours and can be increased up to 400 micrograms. Tablets start at 2 to 4 mg daily and may go up to 8 mg. For people over 40, patches or implants are generally preferred because they carry a lower risk of blood clots compared to oral forms.
Physical changes happen gradually. Breast development often begins within a few weeks as small buds form beneath the nipples. These can be slightly painful and may develop unevenly at first, which is normal. Over months, fat redistributes to the hips and thighs, skin softens, and body hair may thin. These changes unfold over a period of one to three years.
Prostate Cancer Treatment
Estrogen was once the primary alternative to surgical castration for men with advanced prostate cancer. Because prostate cancer cells typically depend on testosterone to grow, estrogen’s ability to suppress testosterone production made it an effective treatment. However, estrogen therapy for prostate cancer fell out of favor due to serious side effects, particularly blood clots and breast enlargement. It has largely been replaced by newer hormone-blocking drugs. Estrogen is now only rarely used for prostate cancer, typically when other hormone treatments have stopped working.
Risks and Side Effects
The most significant risk of taking estrogen is venous thromboembolism, which means blood clots forming in deep veins, particularly in the legs. One review noted roughly a 20-fold increase in clot risk among those taking estrogen. This risk climbs substantially when combined with cigarette smoking, which also raises the chance of strokes and heart attacks. For people over 50, or those with existing health conditions like obesity or a history of clotting disorders, these cardiovascular risks are more pronounced.
Other documented side effects include breast growth (which is an intended effect in gender-affirming care but an unwanted one in other contexts), gallstones, elevated liver enzymes, increased levels of the hormone prolactin, reduced hemoglobin levels, and higher rates of depression compared to the general population. Delivery method matters: patches and implants bypass the liver’s first-pass metabolism, which is why they produce fewer clotting-related complications than pills taken by mouth.
Effects on Fertility
Exogenous estrogen significantly impacts male fertility. Elevated estrogen, or a high estrogen-to-testosterone ratio, disrupts the hormonal signals that drive sperm production. Over time, the cells responsible for producing testosterone in the testes can be depleted, which further impairs the process. Animal studies show that chronically high estrogen levels lead to progressive damage: sperm-producing tissue in the testes can atrophy entirely within months.
For transgender women beginning hormone therapy, fertility counseling and sperm banking before starting treatment are standard recommendations, since the effects on sperm production may not be fully reversible. Interestingly, estrogen at normal physiological levels is actually required for healthy male fertility. The problem arises only when levels become significantly elevated beyond the body’s natural range, whether from medication or from environmental exposure to estrogen-like chemicals.
Estrogen’s Role in Male Sexual Function
The relationship between estrogen and male sexuality is more nuanced than most people expect. Men with low testosterone who also have adequate estrogen levels report better sexual drive than those with low levels of both hormones. In one notable case, a man with both aromatase deficiency (meaning his body couldn’t convert testosterone to estrogen) and low testosterone required both hormones to restore his libido. Neither hormone worked on its own.
This has practical implications for men on testosterone replacement therapy. The goal of treatment should be to maintain not just testosterone but also its downstream metabolites, including estradiol. When testosterone is supplemented without attention to estrogen levels, sexual function may not improve as expected. Estrogen also appears to protect brain areas associated with sexual performance, particularly in men undergoing hormone-suppression treatment for prostate cancer.