After decades of research, the FDA has reversed hormone therapy black box warnings. Explore updated HRT science, timing, benefits, and modern treatment approaches.

Have you heard? The United States Food and Drug Administration (FDA) initiated the removal of "black box" warnings from hormone replacement therapy (HRT) labeling. The November 2025 action prompts patients and providers to investigate the decision's credibility. Breaking down the science of yesterday and the reality of HRT today will help us better understand this long-awaited initiative.

THE SCIENCE OF YESTERDAY

Before the 21st century, hormone therapy was an ongoing subject of study in research laboratories and a first-line treatment option prescribed by clinicians. By 2002, a Women's Health Initiative (WHI) report claimed harmful effects from menopausal hormone therapies, specifically the combination of the synthetic hormones conjugated equine estrogen and medroxyprogesterone acetate. By 2002, the FDA issued a boxed warning, its strongest safety warning, on all estrogen-containing menopausal hormone therapies. Following the widely publicized report and decision, HRT prescription rates plummeted, and patient use rapidly declined. The report's details have been refuted since publication, with misreporting of nonsignificant results, misinterpretation of data, and fundamental selection bias among the contributing issues. The study is now understood to be flawed and failed.

After over 20 years of analysis, research, and advocacy by scientists, medical doctors, and medical institutions and organizations, the FDA assembled the "FDA Expert Panel on Menopause and Hormone Replacement Therapy for Women." In July 2025, the expert panelists met to address the 2002 WHI report and discuss the benefits and risks of HRT. On November 10, 2025, the FDA announced its decision to reverse HRT boxed warning labeling, helping to end the stigma associated with menopausal hormone therapy.

FDA Expert Panel on Menopause and Hormone Replacement Therapy for Women

Roberta Diaz Brinton, PhD

Director, Center for Innovation in Brain Science

Regents Professor, Departments of Pharmacology and Neurology

College of Medicine - Tucson, University of Arizona

Kelly Casperson, MD

Board Certified Urologist

Expert and Advocate for Sexuality and Hormones

Heather Hirsch, MD, MS, NCMP

Board Certified Internist

Founder and CEO, Health by Heather Hirsch MD Collaborative

Howard N. Hodis, MD

Harry J. Bauer and Dorothy Bauer Rawlins Professor of Cardiology

Professor of Medicine and Population and Public Health Sciences

Professor of Molecular Pharmacology and Toxicology

Director, Atherosclerosis Research Unit

Division of Cardiovascular Medicine

Keck School of Medicine

University of Southern California

Barbara Levy, MD, FACOG, FACS, MSCP

Clinical Professor, Obstetrics and Gynecology

The George Washington University School of Medicine and Health Sciences

Voluntary Clinical Professor, Department of Obstetrics, Gynecology, and Reproductive Sciences

University of California, San Diego Health Sciences

Chief Medical Officer, Visana Health

JoAnn E. Mason, MD, DrPH, MACP

Chief, Division of Preventive Medicine

Brigham and Women's Hospital

Professor of Medicine and the Michael and Lee Bell Professor of Women's Health

Harvard Medical School

Mary Jane Minkin, MD

Clinical Professor in the Department of Obstetrics, Gynecology, and Reproductive Sciences

Yale University School of Medicine

JoAnn V. Pinkerton, MD, MSCP, FACOG

Professor of Obstetrics and Gynecology

Division Director Midlife Health

The University of Virginia Health System

Past President and Emeritus Executive Director, The Menopause Society

Chair 2017 NAMS PS on Hormone Therapy

Rachel S. Rubin, MD

Urologist and Sexual Medicine Specialist

Assistant Clinical Professor in Urology and Georgetown University Hospital

Phillip Sarrel, MD

Professor Emeritus of Obstetrics, Gynecology, and Reproductive Sciences and Psychiatry

Yale School of Medicine

James A. Simon, MD, CCD, NCMP, IF

Clinical Professor

George Washington University

Founder and Medical Director, IntimMedicine Specialists

Vonda Wright, MD, MS

Orthopedic Surgeon

Associate Professor of Orthopedic Surgery

University of Central Florida

Founder & CEO - Precision Longevity

WHAT WE KNOW ABOUT HORMONE HEALTHTODAY

Is menopausal hormone therapy safe?

Today, proteomics studies, advanced technologies such as liquid chromatography tandem mass spectrometry, and other analytical techniques and instruments, allow researchers to explore and understand health conditions, assess and develop drugs and treatments, and identify biomarkers that help diagnose diseases. So, is menopausal hormone therapy safe today? Here's what we know:

01 Menopause accelerates the risk of diseases

In 2020, the American Heart Association published a scientific statement regarding the relationship between menopause and cardiovascular disease (CVD), the leading cause of death for women. As it turns out, the risk for CVD increases during menopause due to changes in the body, particularly the decrease in estrogen. The symptoms of menopause, such as hot flashes, poor sleep, and depression, are linked to increased CVD risk as well. Additionally, the decline in estrogen levels experienced during menopause is a significant contributor to the increased risk of osteoporosis and poor bone health, diabetes, and cognitive decline.

02 Timing is everything

The average age of the participants of the WHI study was 12+ years after menopause. The Critical Window Hypothesis, popularly known as the Timing Hypothesis, states that HRT should be prescribed under the age of ~60 and within ~10 years of menopause.

Here's why: when estrogen declines, the body compensates by increasing the number of receptors the estrogen binds to. However, the number of estrogen receptors decreases in response to the permanently low estrogen levels seen during menopause and vascular aging. When you start HRT during the recommended time frame, when estrogen receptor levels are relatively high, then HRT has something to bind to. If you start HRT later in life, when estrogen receptor levels are permanently low, then estrogen has nothing to bind to, which can lead to health complications and adverse outcomes.

03 Hormones are different

Over the last two decades, we have learned that the chemical structure of conjugated equine estrogen (CEE) is vastly different from that of synthetic or natural estradiol. Additionally, horses have other estrogens not found in humans. This means that the molecular roles, actions, and pathways of CEE differ from those of estradiol, and that the WHI study analyzes an entirely different compound from a different organism than the one used in our current standard of care.

Further, medroxyprogesterone acetate, a progestin used in the WHI study, binds differently than the synthetic and bioidentical progestins of today. Micronized progesterone has not been associated with an increase in breast cancer.

04 Menopausal hormone therapy has benefits

Estrogen therapy shows neuroprotective effects on cognitive function and a reduced risk for cognitive decline when initiated before the age of 65. Interestingly, a study published in the American Journal of Primatology found that visuospatial attention significantly improved after 1 month of estrogen therapy in monkeys with surgically removed ovaries and remained improved throughout the 14-month study. Additionally, in patients who have not had a hysterectomy, progestin is added to menopausal HRT to protect the uterus, improve sleep, stabilize mood, and protect bone health and strength.

By restoring declining hormone levels, HRT can be effective for the management of menopausal symptoms like hot flashes and sleep disturbances, which contribute to an increased risk of CVD, along with night sweats, joint pain, and vaginal dryness.

THE FUTURE OF HORMONE THERAPY

It is increasingly clear that the benefits of HRT outweigh the risks in appropriate patients. Unfortunately, the 2003 FDA boxed warning decision continues to have real-world consequences. As we educate ourselves and dismantle the misconceptions associated with HRT, stigma will decrease and access to the treatment option will improve. By understanding HRT's past, we can better equip ourselves with the knowledge and tools to improve longevity and overall well-being today. Esatto Pharma is committed to better health outcomes through evidence-based science and safe, effective treatment options.