In November 2025, the US Food and Drug Administration removed the black-box warning that had been attached to most forms of hormone replacement therapy for over twenty years.
It was an unusually significant moment in modern medicine. The black-box warning is the FDA's most serious, reserved for medications with risks deemed life-threatening. It had appeared on HRT prescriptions since 2003. It had, in the words of multiple senior endocrinologists, kept a generation of women from a treatment that would have meaningfully helped them.
Here is what changed, why it changed, and what it means for women considering HRT today.
The original warning, and the study behind it
The black-box warning on HRT was issued in 2003 in response to early findings from the Women's Health Initiative (WHI), a large randomised trial that began in the 1990s and reported a higher rate of breast cancer, heart disease, and stroke in women taking combined HRT.
The WHI was, at the time, the largest study ever conducted in women's health. Its findings landed with the force of revelation. Within months, HRT prescriptions in the United States fell by an estimated 70%. Many women already on treatment were instructed to stop. A generation of younger women, then entering perimenopause, was advised against considering it.
What was less widely reported, and only fully understood in the years that followed, is that the WHI had significant design problems.
- The average age of participants was 63. Most had been post-menopausal for over a decade when they enrolled. The study was therefore primarily measuring the effects of starting HRT in older women, not the effects of starting it during perimenopause or early menopause.
- The formulations used were dated. The trial used conjugated equine oestrogens (CEE) and synthetic progestins, both of which have since been shown to have a different and worse risk profile than the bioidentical and transdermal preparations now standard in modern practice.
The headline conclusion, that HRT increases breast cancer and cardiovascular risk, was therefore drawn from a population (older women) and a formulation (older preparations) that did not represent the typical use case.
The reanalysis
Over the next twenty years, multiple large reanalyses of the WHI data, plus a substantial body of new research, established a much more nuanced picture.
For women who start HRT within ten years of menopause onset, the data shows a reduction in cardiovascular disease, fractures, and all-cause mortality.
For women who start HRT within ten years of menopause onset, the data shows:
- A reduction in cardiovascular disease risk.
- A reduction in all-cause mortality.
- A reduction in osteoporotic fracture risk.
- A reduction in colorectal cancer.
- A small absolute increase in breast cancer risk that is similar in magnitude to the increase associated with one alcoholic drink per day.
For women who start HRT more than ten years after menopause, the picture is less favourable. The "timing hypothesis," now well established in the literature, holds that the benefits of HRT are tied closely to when treatment is started.
The implication of this is unambiguous. The original WHI study was, in effect, measuring the wrong population. A treatment that is largely beneficial when started in perimenopause was being assessed in women who had been post-menopausal for over a decade.
The 2025 reversal
By 2024, multiple medical bodies, including the North American Menopause Society and the Endocrine Society, had revised their guidelines to recommend HRT as a first-line treatment for symptomatic women in perimenopause and early menopause without contraindications.
In November 2025, the FDA followed. After a multi-year review of the cumulative evidence, the agency removed the black-box warning from oestrogen-containing HRT products. It was the most significant regulatory shift in women's hormonal health in two decades.
The official statement noted that the cumulative evidence "no longer supports the level of warning historically applied," and that the original warning had likely caused "underuse of effective therapy in a population that would benefit."
For women in perimenopause today, this changes the calculus.
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We screen for typical perimenopause presentations and contraindications, and tell you whether HRT is a sensible next conversation.
Take the quiz →What HRT actually is
HRT is a class of treatments that replace the hormones, primarily oestrogen and progesterone, that the body produces less of during the menopausal transition.
Modern HRT is meaningfully different from the formulations used in the WHI:
- Bioidentical hormones, which are chemically identical to the hormones produced by the body, are now standard. The synthetic progestins used in the original WHI are largely no longer prescribed.
- Transdermal delivery, via patches, gels, or sprays, is preferred for oestrogen because it bypasses the liver and is not associated with the increased clotting risk of oral oestrogen.
- Cyclical or continuous progesterone is paired with oestrogen in women who have a uterus, to prevent endometrial overgrowth.
Treatment is typically individualised based on age, symptom pattern, medical history, and personal preference.
Who HRT is for
Modern guidelines support HRT for symptomatic women in perimenopause and early menopause without specific contraindications.
Contraindications, where HRT is not appropriate, include:
- Active or recent breast cancer
- Active hormone-sensitive cancer
- Untreated endometrial cancer
- Active or recent venous thromboembolism
- Active liver disease
- Pregnancy
The list is shorter than is widely believed. Most women who think they cannot take HRT can.
What HRT treats
HRT addresses the underlying hormonal cause of most perimenopausal symptoms, including:
- Sleep disruption
- Mood symptoms (irritability, anxiety, low mood). See perimenopause rage.
- Cognitive symptoms (brain fog, word-finding problems). See perimenopause brain fog.
- Hot flashes and night sweats
- Vaginal dryness and discomfort
- Joint aches
- Reduced libido
It is also increasingly framed as preventive medicine for cardiovascular disease, fracture risk, and possibly cognitive decline, when started during the perimenopausal window.
How to access it
Until recently, accessing HRT required either a sympathetic primary care physician or a referral to a menopause specialist. Wait times for specialist appointments in the US can exceed nine months in many areas.
Telehealth has changed this. Several services, Elin among them, now offer board-certified clinical assessment, prescription, and follow-up entirely remotely. The clinical care model is consistent with what would be received in person from a specialist clinic.
For women whose primary care physician is not trained in modern HRT (which, per recent surveys, is most of them), telehealth specialists are the practical alternative.
A starting point
If you are wondering whether HRT is right for you, the next useful step is a clinical assessment. Our free, 2-minute quiz screens for typical perimenopause presentations and contraindications.