Busting Menopause Myths: How the Women’s Health Initiative Changed Women’s Health Overnight

In Menopause/Perimenopause by Stephanie PrendergastLeave a Comment

By Stephanie A. Prendergast, MPT, , Cofounder, PHRC Los Angeles


It is common knowledge amongst medical professionals and researchers that it takes an average of 17 years for research evidence to reach clinical practice. In 2002 an event occurred that changed healthcare overnight for menopausal women, affecting over 50 million people at the time. Twenty years later, tremendous confusion still exists amongst medical providers and patients about the safety of Hormone Therapy (HT). Women are fearful of HT and suffering unnecessarily. Researchers, medical providers, and advocacy groups are working hard to set the record straight.


What is Menopause and why is Hormone Therapy important? 


Menopause is defined as a 12 month cessation of menses, the average age of menopause is around 52. However, the symptoms and consequences of hormonal deficiencies begin as early as 35 and will continue throughout a woman’s lifespan if left untreated.


Statistics and Facts

  • 6,000 US women enter menopause daily
  • 50 million women are currently menopausal in the US
  • 80% of OBGYN residents admit to being ill-prepared to discuss menopause
  • Less than 13% of PCPs asked their patients about menopause
  • 84% of menopausal women struggle with genital, sexual and urinary discomfort that will not resolve on its own;less than 25% seek help
  • Bloomberg cites – $150B in global productivity loss because of 1 million women leaving the workforce every year due to menopausal symptoms


What is the Women’s Health Initiative (WHI)?


​​The Women’s Health Initiative (WHI) is the largest, randomized longitudinal study to date designed to investigate strategies for the prevention and control of common chronic diseases in postmenopausal women, including cardiovascular disease, cancer, and osteoporotic fractures. This initiative was no small undertaking, it consisted of observational and study and clinical trials with over 161,000 women enrolled at 40 different clinics nationally.


While the WHI includes multiple studies, this blog focuses on the Postmenopausal Estrogen/Progestin Intervention (PEPI) trial of estrogen alone and estrogen in combination with three different progestins.

Risks and benefits of estrogen plus progestin in healthy postmenopausal women

The Breakdown and What You Need To Know


  • Study Design: randomized controlled primary prevention trial
    • 16,608 postmenopausal women with an intact uterus were recruited for the estrogen and progestin arm
    • 10,739 women post-hysterectomy were recruited for the estrogen-only arm
    • Age of women included ranges from 50 – 79 years
  • The study was intended to last longer than it did. The study was discontinued after 5.2 years because the groups receiving estrogen and progesterone showed a slight increased risk in breast cancer and heart disease. 


Overnight, Hormone Therapy Was Abandoned


Before the actual study was published, the media learned about the discontinuation of the study and immediately headlines evoked fear and hysteria amongst medical providers and patients. The results were distorted and misinterpreted and all of a sudden patients on HT believed they would get breast cancer and heart disease. Insurance companies and doctors contacted patients and told them this was in fact true and to immediately stop HT. Just like that, 75% of prescriptions for HT were thrown away.


In the months and years following this news in July of 2002, researchers and clinicians tried to clarify the misinformation. Researchers part of the study tried to re-explain the same data with the right intent. They did not succeed in educating the majority of the country about what actually happened. One example is listed below, a free article available on PubMed.

A critique of Women’s Health Initiative Studies

  • This paper is a re-evaluation of the studies based on the graphic analysis of the the tabulated data from the WHI study above
  • In contrast to the conclusions reached by the WHI treatment of postmenopausal women with estrogen and progestin does not increase the risk of cardiovascular disease, invansive breats cancer, stroke, or venous thromboembolism. 
  • There is disagreement with the claim that an increased risk of stroke existed in women treated with estrogen alone. 


The Facts: What We Know Now


The WHI was a tremendous effort to close the gender gap on the amount of research conducted on women vs white men. There were a number of significant flaws in the study that was halted. The authors themselves have since repudiated their own results, and numerous studies have been released showing the benefits of HT when used in a safe manner, but yet there is confusion and suffering. 


In 2002 the majority of menopausal women in the US were using HT. Today, the number is estimated to be less than 7%. 


What Went Wrong


The information below is a summary from the lecture The Truth About Hormone Therapy, sponsored by the Let’s Talk Menopause patient advocacy group and featuring North American Menopause Society leaders. 


Three main trends caused the negative outcomes in the study mentioned above. First, it is important to note that in the study the increased risk of breast cancer and heart disease was not statistically significant, but also, we now know why there was even a slight risk at all and these risks can be mitigated in clinical practice today. 


  1. The amount and consistent use of progesterone


In this study, daily synthetic progestin was prescribed to women in high doses. Progestin levels vary throughout the month, we now know supplementation should be closer to a woman’s normal cyclical pattern. Women with a uterus need to balance systemic estrogen therapy with a progestin to protect the uterine lining from hyperplasia. Synthetic progestins can be replaced with micronized progesterone which is safe and well tolerated. 


  1. Failure to recognize the impact of age and when to start HT


Systemic estrogen reduces the symptoms of hot flashes, which tend to start as estrogen declines and before a woman is technically in menopause based on the definition (cessation of menses for 12 consecutive months). The study was blinded, meaning women in the study did not know if they were receiving HT or a placebo. Women under the age of 50 were excluded because the estrogen therapy would eliminate their symptoms and they would know they were receiving the actual treatment, therefore ‘unblinding’ them. 


The median age of participants in the study was 65. 21% of women in the study were over the age of 70 and had never taken HT prior. 


Recent studies show that HT is safe and best utilized at the onset of menopausal symptoms. The estrogen component will reduce hot flashes, which are not just an unpleasant symptom but actually an inflammatory event associated with cardiovascular disease. Early usage also helps with insomnia, mood issues, cognitive decline, and prevents bone loss. Experts agree HT should be started within the first three years of menopause to protect bone health, which significantly declines without HT in the first 5 years of menopause.


The risk of cardiovascular disease only occurred in women who started HT for the first time after 10 years in menopause. 


  1. Body Mass Index (BMI) deviations from the regular population


Higher Body Mass Index is linked to higher risk for heart disease in all people. The women in this study had BMIs higher than average BMI for women in the US at the time. Despite this and the age concerns mentioned above, 23 women per 10,000 had heart disease incidence, which was not statistically significant. 


Why does this matter?


Menopause is more than just hot flashes. Hormone Therapy is a safe an effective way to reduce bothersome symptoms (hot flashes, insomnia, mood changes, cognitive decline, bone loss) and also prevent cardiovascular disease, breast cancer, bone fractures, and the Genitourinary Syndrome of Menopause. 


GSM was recently defined in 2014 as it’s own subset of menopause, and because it so closely affects or work as pelvic floor physical therapists we will be covering this in more detail in future posts. However, to get there we have to start here.




Despite current confusion, the experts do agree about HT. The North American Menopause Society, the American Society for Reproductive Medicine, the Endocrine Society and the International Society for the Study of Women’s Sexual Health take the position that HT is safe, especially for recently menopausal women. Grassroots advocacy groups such as Let’s Talk Menopause and My Menopause Matters are trying to help the information get out there. After all, this controversy is exceeding the 17 year rule of medicine changing by clinical practice, and women continue to suffer.


Additional Resources

The Experts Do Agree About Hormone Therapy

Let’s Talk Menopause

The Truth About Hormone Therapy




Cagnacci, A., & Venier, M. (2019). The Controversial History of Hormone Replacement Therapy. Medicina (Kaunas, Lithuania), 55(9), 602. 


Morris, Z. S., Wooding, S., & Grant, J. (2011). The answer is 17 years, what is the question: understanding time lags in translational research. Journal of the Royal Society of Medicine, 104(12), 510–520. 


Rossouw, J. E., Anderson, G. L., Prentice, R. L., LaCroix, A. Z., Kooperberg, C., Stefanick, M. L., Jackson, R. D., Beresford, S. A., Howard, B. V., Johnson, K. C., Kotchen, J. M., Ockene, J., & Writing Group for the Women’s Health Initiative Investigators (2002). Risks and benefits of estrogen plus progestin in healthy postmenopausal women: principal results From the Women’s Health Initiative randomized controlled trial. JAMA, 288(3), 321–333. 



Are you unable to come see us in person in the Bay Area, Southern California or New England?  We offer virtual physical therapy appointments too!


Virtual sessions are available with PHRC pelvic floor physical therapists via our video platform, Zoom, or via phone. For more information and to schedule, please visit our digital healthcare page.

In addition to virtual consultation with our physical therapists, we also offer integrative health services with Jandra Mueller, DPT, MS. Jandra is a pelvic floor physical therapist who also has her Master’s degree in Integrative Health and Nutrition. She offers services such as hormone testing via the DUTCH test, comprehensive stool testing for gastrointestinal health concerns, and integrative health coaching and meal planning. For more information about her services and to schedule, please visit our Integrative Health website page

Melissa Patrick is a certified yoga instructor and meditation teacher and is also available virtually to help, for more information please visit our therapeutic yoga page

Do you enjoy or blog and want more content from PHRC? Please head over to social media!


 YouTube Channel

Twitter, Instagram, Tik Tok

Leave a Comment