Perimenopause History of Treatment Over Decades

The 1940s Through 1960s: Estrogen as a Cultural and Medical Phenomenon

Hormone therapy for menopausal symptoms did not begin as a carefully controlled clinical program. It began as enthusiasm. The FDA approved conjugated equine estrogens (Premarin) in 1942, and by the early 1960s, gynecologists were prescribing estrogen broadly for hot flashes, vaginal atrophy, and mood changes associated with the menopausal transition. Premarin's approval history is documented in FDA records.

Robert Wilson and "Feminine Forever"

The cultural acceleration came in 1966 when gynecologist Robert Wilson published "Feminine Forever," arguing that menopause was an estrogen-deficiency disease and that lifelong estrogen replacement would preserve femininity and health. The book sold over 100,000 copies in its first year. Wilson's framing was later criticized heavily because he had received funding from pharmaceutical manufacturers, but the book's reach reshaped prescribing patterns across the United States.

By 1975, conjugated equine estrogen was among the top five most prescribed drugs in the country. Clinicians were giving unopposed estrogen, meaning estrogen without progestogen, to women regardless of uterine status.

The Endometrial Cancer Signal: 1975

The enthusiasm met its first major check in 1975, when two independent studies published in the New England Journal of Medicine demonstrated that unopposed estrogen roughly quadrupled endometrial cancer risk. Ziel and Finkle's landmark paper showed an odds ratio of 7.6 for endometrial carcinoma in women using conjugated estrogens. Prescribing of unopposed estrogen dropped sharply among women with intact uteri. The field rapidly pivoted to adding a progestogen, creating what would become combined estrogen-progestogen therapy (EPT).

The 1980s: Combined Therapy, Cardiovascular Hope, and Observational Data

The 1980s produced a wave of observational studies suggesting that estrogen therapy might protect the heart. The Nurses' Health Study, which eventually enrolled over 121,000 women, became the most cited source for this hypothesis. Early analyses suggested women using postmenopausal hormones had roughly 50% lower coronary heart disease risk compared with non-users. The Nurses' Health Study cardiovascular findings are summarized in Stampfer et al., NEJM 1991.

Adding Progestogen: The MPA Question

The addition of medroxyprogesterone acetate (MPA) to estrogen regimens protected the uterus but raised questions about whether MPA would blunt estrogen's proposed cardiovascular benefit. Debate about progestogen type, dose, and route occupied gynecology and endocrinology journals throughout the decade. Cyclic versus continuous-combined regimens were compared in small trials, with the continuous-combined approach (daily estrogen plus daily MPA) gaining traction by the late 1980s because it eliminated monthly withdrawal bleeding for most women after 6 to 12 months.

Non-Hormonal Options in the 1980s

Clonidine, originally an antihypertensive, was used off-label for vasomotor symptoms throughout this decade. Studies showed modest benefit: a 1987 transdermal clonidine trial in the BMJ showed roughly a 46% reduction in hot flash frequency compared with 28% for placebo. See Clayden et al. BMJ data. The effect size was meaningful but far below what estrogen provided. Behavioral strategies including cooling techniques and layered clothing were standard supportive advice but carried no randomized trial support at the time.

The 1990s: HERS, PEPI, and Building Toward a Randomized Answer

By the early 1990s, the observational case for hormone therapy as cardioprotective was strong enough that the National Institutes of Health funded two definitive randomized trials: the Postmenopausal Estrogen/Progestin Interventions (PEPI) trial and the Heart and Estrogen/progestin Replacement Study (HERS).

PEPI Trial Results (1995)

The PEPI trial (N=875) randomized postmenopausal women to placebo or one of four active hormone regimens for three years. The primary outcomes were cardiovascular risk factors. Active regimens improved HDL cholesterol by 1.2 to 5.6 mg/dL depending on the regimen, reduced LDL, and improved fibrinogen levels compared with placebo. Writing Group for the PEPI Trial, JAMA 1995. These biomarker improvements reinforced optimism that a cardiovascular outcome benefit would follow.

HERS Delivers a Shock (1998)

HERS enrolled 2,763 postmenopausal women with established coronary disease and randomized them to conjugated equine estrogen 0.625 mg plus MPA 2.5 mg daily or placebo. After 4.1 years, there was no reduction in primary coronary events. Worse, year one showed a statistically significant increase in events in the hormone group before a possible late benefit emerged. Hulley et al., JAMA 1998. HERS dismantled the idea that HT should be initiated for secondary cardiovascular prevention.

SSRIs Enter the Picture

The 1990s also saw the first serious off-label use of SSRIs for vasomotor symptoms. Paroxetine and venlafaxine were studied in small trials and showed 30 to 60% reductions in hot flash frequency. These were particularly relevant for breast cancer survivors who could not use estrogen. The option expanded the clinical toolkit meaningfully, though the effect size remained below that of estrogen.

2002: The WHI and the Great Prescribing Collapse

No single publication changed perimenopause and menopause prescribing more than the Women's Health Initiative. The WHI was a randomized, placebo-controlled trial with two hormone arms: a combined EPT arm (CEE 0.625 mg plus MPA 2.5 mg, N=16,608) and an estrogen-alone arm for women without a uterus (CEE 0.625 mg alone, N=10,739). The EPT arm was stopped early in July 2002, after a mean 5.2 years of follow-up.

What the WHI Found

The WHI EPT arm showed a hazard ratio of 1.26 for invasive breast cancer, 1.29 for coronary heart disease, 1.41 for stroke, and 2.13 for pulmonary embolism compared with placebo. Benefits included reduced colorectal cancer (HR 0.63) and hip fracture (HR 0.66). Rossouw et al., JAMA 2002.

The Media Interpretation Problem

Newspapers reported the breast cancer finding as a dramatic absolute risk increase. The actual absolute risk was 8 additional breast cancers per 10,000 women per year, a small increase that was lost in the headline coverage. The Menopause Society would later note: "The WHI findings were frequently misrepresented in media and clinical settings, leading to unnecessary fear and undertreatment of symptomatic women." U.S. Hormone therapy prescriptions dropped by approximately 50% between 2002 and 2004.

Women with moderate to severe vasomotor symptoms were left undertreated. Some turned to compounded bioidentical hormones, which had no randomized trial support and no FDA approval, but which were marketed aggressively as "natural" and therefore safer. The FDA has consistently stated that compounded hormone preparations lack evidence of safety or efficacy equivalent to approved products. FDA statement on compounded hormones.

2002 to 2012: Reanalysis, the Timing Hypothesis, and Partial Rehabilitation

The decade following the WHI publication produced intensive reanalysis. Researchers noted that the average WHI participant was 63 years old at enrollment, roughly 10 years past the final menstrual period. This was not the typical symptomatic perimenopausal or early postmenopausal woman seeking treatment.

The Timing Hypothesis (Estrogen Window)

Naftolin, Clarkson, and colleagues proposed the "timing hypothesis," arguing that estrogen started close to menopause, when arterial walls are still responsive, might be cardioprotective, while estrogen started in older women with pre-existing atherosclerosis might destabilize plaques. Clarkson et al. Published supporting primate data in Circulation.

The WHI reanalysis by age subgroup showed that women who initiated hormone therapy within 10 years of menopause had a non-significant trend toward reduced cardiovascular events (HR 0.76, 95% CI 0.50 to 1.16), while women who initiated 20 or more years after menopause had elevated risk (HR 1.28). Rossouw et al., JAMA 2007. The absolute confidence intervals were wide, but the pattern was consistent and clinically meaningful.

The Estrogen-Alone WHI Arm: A Different Story

The estrogen-alone arm of the WHI, which ran through 2004, showed no significant increase in breast cancer risk (HR 0.77, 95% CI 0.59 to 1.01) and a non-significant reduction. This finding complicated the narrative that "hormones cause breast cancer" and pointed specifically at MPA as the progestogen of concern. Anderson et al., JAMA 2004.

2012 to 2020: Transdermal Estrogen, Micronized Progesterone, and Refined Risk Stratification

As the WHI reanalysis solidified the timing hypothesis, guidelines began to shift. The key clinical refinements of this era centered on route of administration and progestogen type, not just estrogen dose.

Transdermal Estrogen and Thrombosis Risk

Oral estrogen undergoes first-pass hepatic metabolism, producing supraphysiologic hepatic estrogen concentrations that increase coagulation factors and C-reactive protein. Transdermal estradiol, delivered as a patch, gel, or spray, bypasses hepatic first-pass and does not significantly increase clotting factor production. Observational data, particularly from the French E3N cohort (N=80,391), showed that transdermal estradiol carried no significant increase in venous thromboembolism risk (OR 0.9, 95% CI 0.6 to 1.5), while oral estrogen carried an OR of 1.7. Canonico et al., Circulation 2007.

Micronized Progesterone vs. MPA

The E3N cohort also differentiated progestogen type. Women using transdermal estradiol combined with micronized progesterone (Prometrium in the U.S.) showed no significant increase in breast cancer risk after 5.8 years of follow-up, while those using synthetic progestogens including MPA showed a modest increase. Fournier et al., Breast Cancer Research and Treatment 2008. This observational finding, though not from a randomized trial, drove a shift in prescribing toward micronized progesterone for women with an intact uterus.

SSRI/SNRI Formal Approval

In 2013, the FDA approved low-dose paroxetine mesylate 7.5 mg (Brisdelle) as the first non-hormonal prescription therapy specifically approved for vasomotor symptoms. FDA approval record for Brisdelle. The effect size was modest: roughly 1.8 fewer hot flashes per day versus 1.0 for placebo at 12 weeks, but the approval provided a regulated alternative for women who could not or would not use hormones.

Gabapentin and Cognitive Side Effects

Gabapentin (off-label, 300 mg TID) had accumulated reasonable trial evidence for hot flash reduction by the 2010s, with a 2006 Obstetrics and Gynecology study showing a 45% reduction in hot flash composite score versus 29% for placebo. Guttuso et al., Obstetrics and Gynecology 2003. Cognitive dulling and dizziness limited long-term patient acceptance, particularly in women who remained employed.

2020 to Present: Neurokinin Antagonists, Personalized Prescribing, and the 2023 Guidelines

The most recent chapter in perimenopause treatment history is driven by a new pharmacological target: the neurokinin B (NKB) pathway. NKB stimulates kisspeptin/neurokinin B/dynorphin (KNDy) neurons in the hypothalamic thermoregulatory center, which become overactive during estrogen withdrawal. Blocking the NK3 receptor suppresses this pathway without involving estrogen.

Fezolinetant (Veozah): The First NK3 Antagonist

Fezolinetant was approved by the FDA on May 12, 2023 for moderate to severe vasomotor symptoms due to menopause. In the SKYLIGHT 1 trial (N=547), fezolinetant 45 mg once daily reduced mean daily moderate to severe hot flash frequency by 4.0 events at week 4 versus 2.5 for placebo (P<0.001), with sustained benefit through week 52. FDA approval announcement for Veozah. Fezolinetant requires liver function monitoring due to transaminase elevations seen in a small percentage of patients.

The 2023 Menopause Society Position Statement

The Menopause Society (formerly the North American Menopause Society) released its 2023 Position Statement with language directly addressing the post-WHI overcorrection. The statement reads: "Hormone therapy is the most effective treatment for vasomotor symptoms and is approved by the FDA for this indication. For women aged younger than 60 years or within 10 years of menopause onset without contraindications, the benefit-risk ratio is favorable for treatment of bothersome vasomotor symptoms." The Menopause Society 2023 Position Statement.

The statement also formally endorsed transdermal estradiol and micronized progesterone as preferred formulations based on the E3N and related observational data.

Current Prescribing Field: Still Undertreated

Despite the guideline rehabilitation, data from the 2020 SWAN (Study of Women's Health Across the Nation) follow-up suggest that fewer than 10% of eligible symptomatic women currently use prescription hormone therapy, compared with approximately 38% in 1999 to 2000. SWAN longitudinal data, Menopause journal. The treatment gap reflects persistent fear from the 2002 WHI headlines, clinician uncertainty about updated evidence, and systemic barriers to menopause-specialized care.

Treatment Options by Era: A Practical Summary

| Era | Primary Treatment | Regulatory Status | Key Evidence | |-----|-----------------|-------------------|--------------| | 1940s to 1960s | Oral conjugated estrogen (Premarin) | FDA approved 1942 | Case series, expert opinion | | 1975 onward | Combined estrogen plus progestogen | Widely prescribed | Observational; endometrial cancer data | | 1995 | CEE plus MPA (PEPI validated biomarkers) | Approved | PEPI RCT, N=875 | | 1998 | No secondary CV prevention role | Guideline change | HERS RCT, N=2,763 | | 2002 | WHI EPT arm halted; prescribing collapses | Label updates | WHI RCT, N=16,608 | | 2007 onward | Transdermal estradiol plus micronized P4 | Approved | E3N cohort, N=80,391 | | 2013 | Paroxetine 7.5 mg (Brisdelle) | First FDA-approved non-hormonal | Randomized trials | | 2023 | Fezolinetant (Veozah) NK3 antagonist | FDA approved May 2023 | SKYLIGHT 1, N=547 |