Cited by 15,889Menopause: Health Impacts and TreatmentsEstrogen and related hormone effectsPhytoestrogen effects and research

Risks and Benefits of Estrogen Plus Progestin in Healthy Postmenopausal Women: Principal Results From the Women's Health Initiative Randomized Controlled Trial

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Writing Group for the Women's Health Initiative Investigators·2002·JAMA: The Journal of the American Medical Association

Abstract

CONTEXT: Despite decades of accumulated observational evidence, the balance of risks and benefits for hormone use in healthy postmenopausal women remains uncertain. OBJECTIVE: To assess the major health benefits and risks of the most commonly used combined hormone preparation in the United States. DESIGN: Estrogen plus progestin component of the Women's Health Initiative, a randomized controlled primary prevention trial (planned duration, 8.5 years) in which 16608 postmenopausal women aged 50-79 years with an intact uterus at baseline were recruited by 40 US clinical centers in 1993-1998. INTERVENTIONS: Participants received conjugated equine estrogens, 0.625 mg/d, plus medroxyprogesterone acetate, 2.5 mg/d, in 1 tablet (n = 8506) or placebo (n = 8102). MAIN OUTCOMES MEASURES: The primary outcome was coronary heart disease (CHD) (nonfatal myocardial infarction and CHD death), with invasive breast cancer as the primary adverse outcome. A global index summarizing the balance of risks and benefits included the 2 primary outcomes plus stroke, pulmonary embolism (PE), endometrial cancer, colorectal cancer, hip fracture, and death due to other causes. RESULTS: On May 31, 2002, after a mean of 5.2 years of follow-up, the data and safety monitoring board recommended stopping the trial of estrogen plus progestin vs placebo because the test statistic for invasive breast cancer exceeded the stopping boundary for this adverse effect and the global index statistic supported risks exceeding benefits. This report includes data on the major clinical outcomes through April 30, 2002. Estimated hazard ratios (HRs) (nominal 95% confidence intervals [CIs]) were as follows: CHD, 1.29 (1.02-1.63) with 286 cases; breast cancer, 1.26 (1.00-1.59) with 290 cases; stroke, 1.41 (1.07-1.85) with 212 cases; PE, 2.13 (1.39-3.25) with 101 cases; colorectal cancer, 0.63 (0.43-0.92) with 112 cases; endometrial cancer, 0.83 (0.47-1.47) with 47 cases; hip fracture, 0.66 (0.45-0.98) with 106 cases; and death due to other causes, 0.92 (0.74-1.14) with 331 cases. Corresponding HRs (nominal 95% CIs) for composite outcomes were 1.22 (1.09-1.36) for total cardiovascular disease (arterial and venous disease), 1.03 (0.90-1.17) for total cancer, 0.76 (0.69-0.85) for combined fractures, 0.98 (0.82-1.18) for total mortality, and 1.15 (1.03-1.28) for the global index. Absolute excess risks per 10 000 person-years attributable to estrogen plus progestin were 7 more CHD events, 8 more strokes, 8 more PEs, and 8 more invasive breast cancers, while absolute risk reductions per 10 000 person-years were 6 fewer colorectal cancers and 5 fewer hip fractures. The absolute excess risk of events included in the global index was 19 per 10 000 person-years. CONCLUSIONS: Overall health risks exceeded benefits from use of combined estrogen plus progestin for an average 5.2-year follow-up among healthy postmenopausal US women. All-cause mortality was not affected during the trial. The risk-benefit profile found in this trial is not consistent with the requirements for a viable intervention for primary prevention of chronic diseases, and the results indicate that this regimen should not be initiated or continued for primary prevention of CHD.

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  • Hormone therapy is effective in treating hot flashes, but its use is contraindicated for individuals initiating hormone therapy more than 10 years from menopause onset or older than 60 years, and with a history of breast cancer, uterine cancer, thromboembolic, or cardiovascular diseases.

    “Although hormone therapy is effective in treating hot flashes, its use is contraindicated for individuals initiating hormone therapy more than 10 years from menopause onset or older than 60 years, and with a history of breast cancer, uterine cancer, thromboembolic, or cardiovascular diseases.10,11,12”

    From Self-Administered Hypnosis vs Sham Hypnosis for Hot Flashes (2025) · cites this paper as [10]

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  • The WHI reported increased risks of myocardial infarction, stroke, invasive breast cancer, pulmonary emboli, and deep vein thrombosis during 5 years of treatment with conjugated equine estrogen and medroxyprogesterone acetate (Prempro).

    “The WHI reported increased risks of myocardial infarction, stroke, invasive breast cancer, pulmonary emboli, and deep vein thrombosis during 5 years of treatment with conjugated equine estrogen and medroxyprogesterone acetate (Prempro®) [69].”
  • Five years of hormone therapy (Prempro) reduced the risk of clinical vertebral fractures and hip fractures by 34%.

    “The Woman’s Health Initiative (WHI) found that 5 years of HT (Prempro®) reduced the risk of clinical vertebral fractures and hip fractures by 34 % and other osteoporotic fractures by 23 % [69].”
  • Five years of hormone therapy (Prempro) reduced the risk of other osteoporotic fractures by 23%.

    “The Woman’s Health Initiative (WHI) found that 5 years of HT (Prempro®) reduced the risk of clinical vertebral fractures and hip fractures by 34 % and other osteoporotic fractures by 23 % [69].”
  • All of about 90 HIV vaccines that succeeded in animals failed in humans.

    “Yet all of about 90 HIV vaccines that succeeded in animals failed in humans.55”

    From The Flaws and Human Harms of Animal Experimentation (2015) · cites this paper as [55]

    Our copy discusses an estrogen-plus-progestin trial in postmenopausal women, including earlier trials in nonhuman primates (Abstract; page unavailable). Searches for HIV vaccines and the figure of about 90 found no passage addressing whether vaccines succeeded in animals but failed in humans. (LLM, conf=0.78)

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Research works printed but not linked: 6

  1. [5]5. Rijpkema AH, van der Sanden AA, Ruijs AH. Ef- fects of postmenopausal estrogen-progesterone therapy on serum lipids and lipoproteins: a review. Ma- turitas. 1990;12:259-285.
  2. [18]18. Cox DR. Regression analysis and life tables. J R Stat Soc. 1972;34:187-220.
  3. [23]23. Writing Group for the PEPI Trial. Effects of estro- gen or estrogen/progestin regimens on heart disease risk factors in postmenopausal women. JAMA. 1995; 273:199-208.
  4. [25]25. Schulman SP, Thiemann DR, Ouyang P, et al. Ef- fects of acute hormone therapy on recurrent ische- mia in postmenopausal women with unstable an- gina. J Am Coll Cardiol. 2002;39:231-237.
  5. [29]29. Hodis HN, Mack WJ, Lobo RA, et al. Estrogen in the prevention of atherosclerosis: a randomized, double-blind controlled trial. Ann Intern Med. 2001; 135:939-953.
  6. [43]43. Writing Group for the PEPI Trial. Effects of hormone therapy on bone mineral density: results from the Postmenopausal Estrogen/Progestin Interventions (PEPI) Trial. JAMA. 1996;275:1389- 1396.

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Authors
Writing Group for the Women's Health Initiative Investigators
Affiliations
National Heart, Lung, and Blood Institute (US)
Corresponding author
Writing Group for the Women's Health Initiative Investigators
Venue
JAMA: The Journal of the American Medical Association
Published
2002-07-17
Volume
288
Issue
3
Pages
321-333
ISSN
  • 0002-9955 (ISSN-L)
  • 0098-7484
  • 1538-3598
OpenAlex
W1593442063
Cited by
15,889
References
54
Citations by year
2026: 283 · 2025: 348 · 2024: 342 · 2023: 365 · 2022: 459 · 2021: 465 · 2020: 452 · 2019: 453 · 2018: 455 · 2017: 452 · 2016: 486 · 2015: 572 · 2014: 546 · 2013: 688 · 2012: 713
FWCI
647.30
Type
journal article
Language
en
Open access
Locations
  • JAMA (publishedVersion)
  • PubMed (publishedVersion)
  • eScholarship (California Digital Library) (submittedVersion)
  • eScholarship@UMassChan (submittedVersion)
Funders
Pfizer
Topics
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Menopause: Health Impacts and Treatments
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Estrogen and related hormone effects
  • Health Sciences › Medicine › Pathology and Forensic Medicine › Phytoestrogen effects and research
Keywords
estrogen plus progestin, conjugated equine estrogens, medroxyprogesterone acetate, postmenopausal women, hormone replacement therapy, coronary artery disease, invasive breast cancer, stroke, pulmonary embolism, endometrial cancer, colorectal cancer, hip fracture, mortality, benefits and risks, Women's Health Initiative, early trial termination, primary prevention
MeSH terms
Aged, Breast Neoplasms, Coronary Disease, Estrogens, Conjugated (USP), Female, Humans, Middle Aged, Myocardial Infarction, Pulmonary Embolism, Risk, Thrombosis, Colorectal Neoplasms, Estrogen Replacement Therapy, Proportional Hazards Models, Survival Analysis, Endometrial Neoplasms, Treatment Outcome, Medroxyprogesterone Acetate, Postmenopause, Stroke, Clinical Trials Data Monitoring Committees, Progesterone Congeners, Fractures, Bone

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