Hormone replacement therapy uses medication to supplement hormone production in the human body. The vast majority of HRT is for menopause symptoms. It's used more rarely for testosterone deficiencies or as part of gender-affirming care for transgender people. HRT formulations may include injections, patches, gels, creams, sprays, and pills.
HRT was extremely popular for treating menopausal symptoms and lowering certain women's health risks in the 1990s, but its use plummeted in the early 2000s after the well-known Women's Health Initiative found it increased the incidence of breast cancer, heart disease, and stroke in some women. Those findings were subsequently found to be overblown and largely disproved: In 2025, the US Food and Drug Administration removed its warning label about such risks, and in 2026, supply of estradiol patches—which have lower blood clotting risks than other estrogen formulations—has been unable to keep up with demand.
Testosterone therapy for men with "low T"—typically defined as below 300 nanograms per deciliter of blood—has been buoyed by recent positive cardiovascular safety data and the FDA's 2025 related decision to drop its cardiovascular warning. Prescriptions for testosterone, though low overall, roughly doubled for injectable formulations between 2019 and 2025.
The third typical use for HRT is gender-affirming care. About 1% of America's adults, or more than 2 million people, identify as transgender and estimates vary on what percentage of the transgender community may use HRT. Transgender women may use estrogen and anti-androgens (to suppress testosterone) and transgender men may use testosterone, causing physiological changes somewhat similar to puberty.
Hours of research by our editors, distilled into minutes of clarity.
This lengthy video features a board-certified OB/GYN based in Texas who provides a thorough overview of the different formulations for HRT, used to treat symptoms including hot flashes, vaginal dryness, and mood swings, and the pros and cons of each. She also discusses modern synthetic options versus the older formulation extracted from the urine of confined pregnant horses.
The treatments can treat symptoms like hot flashes and vaginal dryness at varying doses. Progestogen, another hormone, is also typically prescribed with estrogen because estrogen alone can thicken the uterus lining, which elevates the risk of developing endometrial cancer.
The agency removed the label in 2025, reversing its 2003 decision to warn women about HRT's links to stroke risk, developing cancer, and heart disease. Years of accumulating research have found that the risks had been overstated and unnecessarily deterred hormone therapy use. The agency still warns against using certain estrogen-alone products, however, due to elevated endometrial cancer risk.
In the early 2000s, Women's Health Initiative studies indicated HRT increased risk of breast cancer, heart disease, and stroke in some women—so many physicians stopped prescribing it to help with menopause symptoms. But further research has concluded that much of the elevated risk was overblown and that it was also disproportionately seen in women in their 70s who had been taking an older HRT formulation.
A recent analysis investigating the effects of menopause and HRT use on mental health, cognition, and brain health suggested HRT did little or nothing to aid with mental health and sleep. But the researchers caution that, among other data gaps, they didn't have information on which HRT formulations were used among their nearly 125,000 participants, so results may have varied by drug treatment.
Symptoms of menopause and perimenopause (the premenopause period) can be varied enough that clinicians dismiss them in patients in their mid-30s and onward as just a symptom of hormone level change. In this story, a woman's itching was dismissed as a hormonal change, but after two years and 11 separate doctor consultations, was diagnosed as cancer. (Some users may experience a paywall.)
The marketing shift and accompanying awareness campaigns, both by the company behind the first testosterone product approved by the FDA, changed the landscape for testosterone product demand. Testosterone is often considered low when it's below 300 nanograms per deciliter of blood. (Some users may experience a paywall.)
Many primary care clinicians may not be familiar with testosterone testing protocols and treatments, but online testosterone clinics are proliferating, with names like DudeMeds. COVID-era restrictions loosened remote prescribing rules, allowing them to expand online widely, though those more lenient prescribing policies are slated to expire in December 2026 unless they're renewed. (Some users may experience a paywall.)
Though demand for an injectable formulation of testosterone roughly doubled between 2019 and 2025, testosterone prescriptions still remain very uncommon—adding up to less than 2 per 100,000 prescriptions in 2025.
The change came a decade after the FDA added the label. Recent work, including a gold-standard randomized trial, found that men receiving the products had similar cardiovascular risk levels as men taking placebo products. Testosterone, however, may hold other health risks, including infertility.
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