Enough of “Menopause” Already! All the “Action” is in Perimenopause

February 26, 2025

Jerilynn C. Prior BA, MD, FRCPC

If I were to consider women’s experiences, I would view menopause (that starts after a year without flow) as peacefully gazing at the horizon across a vast and calm sea. Perimenopause, however, is like the crashing of chaotic ocean waves during a hurricane.

Why do we hear so little about perimenopause?
First of all, because women usually think “menopause” means both perimenopause and menopause. We have discussed this wrong, and unnecessary, confusion before.

Second, because there is no perimenopause “magic bullet” for symptom treatment that Big Pharma and gynecology can promote. All guidelines assert that Menopausal Hormone Therapy (MHT) treats perimenopausal vasomotor symptoms (VMS, hot flushes/night sweats)¹. However, no scientific studies have shown that MHT is safe or effective in perimenopause. Why take estrogen when our one estrogen is already high?

Third, because today’s perimenopausal women (who may be 35-55 years old) look too young to be starting into the process of “reproductive aging.” Plus, we equate hot flushes, night sweats and sleep problems with ‘estrogen deficiency’ and with OLD women.

Finally, we hear so little about perimenopause because it is complex, relates to aging (which younger women don’t want to hear), and it has to do with unmentionable things like heavy flow, incontinence and mood swings. Plus, women fear being labelled ‘crazy.’

What really changes in perimenopause?
The short answer is: just about everything!

Cycles get shorter before they become unpredictable. Sleep is snatched from us in the middle of the night; pursuing rest becomes a never-ending task. We finish our period and suddenly we are flooding! We view ourselves as young, and at least a bit attractive, yet we are facing loss of fertility and all the lumpy, wrinkly things associated with old age. We may feel foggy-headed, suddenly furious or inexplicably sad. Oh no! We are leaking before we reach the toilet. And, sex may become either too much work, or maybe the last thing we care about.

Perimenopause and menopause are opposites
The calm seas of menopause are low and steady estrogen and progesterone levels (for the first time since childhood). But in perimenopause the huge and symptom-producing change is because estrogen levels soar^{2 3}, and then crash down. These higher average estrogen levels²and especially the down-swings of estrogen, cause VMS⁴, rapid bone loss⁵ and even depression⁶.

While perimenopausal estrogen levels are going crazy, progesterone is gradually taking a hike³. Ovulating requires more coordination than the changing perimenopausal cycle can often muster. It is higher estrogen with lower progesterone levels that trigger flooding menstruation⁷, an experience a third of perimenopausal women have⁸. Note that gynecology blames flooding on fibroids⁹. It is also likely higher estrogen that causes urinary incontinence (based on its starting in estrogen-treated women in the randomized Women’s Health Initiative estrogen-only trial)¹⁰.

Why does estrogen become high and crashing in perimenopause?
We know that the normal menstrual cycle is a carefully coordinated system managed by the hypothalamus¹¹ to help us deal with stressors¹². Early in midlife, that coordinated system starts unraveling. Why? Because it must, for us to be able to “get rid” of the surplus estrogen-making ovarian follicles that would otherwise give us periods in old age. So, without the normal feedback, more small follicles grow, each make some estrogen and then are absorbed. If several small follicles make estrogen at the same time there is a peak from which levels drop as they stop growing and disappear.

Perimenopause is worth talking about
Why?

For two reasons: perimenopause ends, and we can now safely treat its night sweats and sleep problems.
Almost always a highly problematic perimenopause becomes a peaceful menopause. Although perimenopause may last from two to more than 12 years, we eventually graduate into menopause. We may have the odd hot flush for a few years, but it’s a cake-walk compared to perimenopause.

Although estrogen-based MHT hasn’t been shown to help symptomatic perimenopause, we now have strong (and Canadian) evidence that progesterone effectively treats perimenopausal night sweats and sleep problems¹.

Reference List
1. Prior JC, Cameron A, Fung M, et al. Oral micronized progesterone for perimenopausal night sweats and hot flushes a Phase III Canada-wide randomized placebo-controlled 4 month trial. Sci Rep 2023;13(1):9082. doi: https://www.nature.com/articles/s41598-023-35826-w [published Online First: 20230605]
2. Prior JC. Perimenopause: The complex endocrinology of the menopausal transition. Endocrine Reviews1998;19:397-428.
3. Santoro N, Rosenberg J, Adel T, et al. Characterization of reproductive hormonal dynamics in the perimenopause. Journal of Clinical Endocrinology and Metabolism 1996;81:4:1495-501.
4. Freedman RR. Menopausal hot flashes: mechanisms, endocrinology, treatment. J Steroid BiochemMol Biol2014;142:115-20.
5. Berger C, Langsetmo L, Joseph L, et al. Change in bone mineral density as a function of age in women and men and association with the use of antiresorptive agents. Can Med Assoc J 2008;178 1660-68.
6. Schmidt PJ, Ben DR, Martinez PE, et al. Effects of Estradiol Withdrawal on Mood in Women With Past Perimenopausal Depression: A Randomized Clinical Trial. JAMA Psychiatry 2015;72(7):714-26.
7. Moen MH, Kahn H, Bjerve KS, et al. Menometrorrhagia in the perimenopause is associated with increased serum estradiol. Maturitas 2004;47(2):151-55.
8. Kaufert PA. Menstruation and menstrual change: women in midlife. Health Care Women Int 1986;7(1-2):63-76.
9. Paramsothy P, Harlow SD, Greendale GA, et al. Bleeding patterns during the menopausal transition in the multi-ethnic Study of Women's Health Across the Nation (SWAN): a prospective cohort study. BJOG2014;121(12):1564-73. doi: 10.1111/1471-0528.12768 [published Online First: 2014/04/17]
10. Hendrix SL, Cochrane BB, Nygaard IE, et al. Effects of estrogen with and without progestin on urinary incontinence. JAMA 2005;293(8):935-48.
11. Prior JC. Women’s Reproductive System as Balanced Estradiol and Progesterone Actions—a revolutionary, paradigm-shifting concept in women’s health. Drug Discovery Today: Disease Models 2020;32:31-40. doi: https://doi.org/10.1016/j.ddmod.2020.11.005
12. Prior JC. Adaptive, reversible, hypothalamic reproductive suppression: More than functional hypothalamic amenorrhea. Frontiers in Endocrinology 2022;13 doi: 10.3389/fendo.2022.893889

February Highlights

In early February, the CeMCOR team attended a screening of the PBS Documentary film, ‘The M Factor’, organized by The Pink Zones at the Kitsilano Neighbourhood House in Vancouver. The screening was followed by a panel discussion between Dr. Jerilynn Prior, Dr. Heidi Lescanec, and Dr. Sukpreet Patel, moderated by Dr. Thara Vayali.

From left to right–Dr. Thara Vayali, Dr. Jerilynn Prior, Dr. Heidi Lescanec, and Dr. Sukhpreet Patel

The film highlighted the confusion, lack of information, and challenges many face when navigating the menopause transition. Some experience it as a smooth shift, while for others, it can feel like a storm that requires more support. Events like these bring women+ together to share knowledge, break taboos, change misconceptions, and advocate for better healthcare.

At CeMCOR, we offer multiple tools and resources to help support you through these life phases. We’re grateful to be part of this conversation and look forward to more opportunities to support, educate, and empower!

“Awareness of perimenopausal changes, workplace accommodation, and progesterone therapy, if needed, will allow all midlife women to survive and thrive”
- Dr. Jerilynn Prior

Estrogen’s Storm Season: Stories of Perimenopause

Estrogen's Storm Season

by Dr. Jerilynn C Prior

New second edition available

Estrogen’s Storm Season is now available in BOTH print and eBook (Mobi and ePUB) versions!

All royalties are recieved in our Endowment fund (overseen by UBC) and support CeMCOR's research and future.

It is full of lively, realistic stories with which women can relate and evidence-based, empowering perimenopause information. It was a finalist in 2006 for the Independent Publisher Book Award in Health.

Purchase your ebook copy via our Amazon Kindle or
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Paperback copies (with updated insert) still available here.

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