Primary Causes & Action Plans

FSH (Follicle-Stimulating Hormone)

Rises as ovarian reserve declines; defines perimenopause stage
FSH rises dramatically during perimenopause as the ovaries respond less to FSH signaling. FSH level indicates your stage in the perimenopause transition: early (FSH <10), middle (FSH 10-40), late (FSH >40). Testing FSH at multiple points during the cycle reveals the pattern.
Target Early perimenopause: FSH 10-40. Late: >40
Suggested Action Plan

FSH cannot be directly lowered. Instead, optimize progesterone and estradiol to manage symptoms. If FSH is already very high (>40), you may be approaching menopause. Cycle your bioidentical hormones if using them.

Estradiol (Serum)

Fluctuates wildly in perimenopause; drives hot flashes and mood symptoms
Estradiol swings widely during perimenopause, producing hot flashes, night sweats, and mood destabilization. Testing estradiol at multiple points in the cycle (follicular and luteal phases) reveals the pattern. Some women need estrogen support; others need progesterone to balance excessive estrogen.
Target Follicular: 30-100 pg/mL. Luteal: 50-200 pg/mL
Suggested Action Plan

If estradiol is low, bioidentical estrogen patches can be used. If estradiol is normal but wildly fluctuating, progesterone support is often more helpful. Retest every 2-3 months during dose adjustments.

Progesterone

Collapses first in perimenopause; deficiency drives many symptoms
Progesterone is the first hormone to decline in perimenopause, often while estradiol remains normal. Low progesterone causes anxiety, insomnia, hot flashes, and mood swings. Progesterone restoration often resolves these symptoms completely.
Target Luteal phase: 5-20 ng/mL (normal); >10 ng/mL is typically therapeutic
Suggested Action Plan

If progesterone is low, bioidentical micronized progesterone (capsules or cream) is typically given 100-200 mg daily during the luteal phase. Many women feel dramatically better within days to weeks of starting progesterone.

Thyroid Panel (TSH, Free T4)

Thyroid often declines with menopause transition; can amplify perimenopause symptoms
Thyroid function often declines alongside ovarian function during perimenopause. This produces additional fatigue, weight gain, dry skin, and mood symptoms on top of estrogen/progesterone imbalance. Screening thyroid is essential during perimenopause.
Target TSH: 1.0-2.5 mIU/L. Free T4: 1.0-1.5 ng/dL
Suggested Action Plan

If thyroid function is low, thyroid hormone replacement should be started. Optimizing thyroid function often significantly improves perimenopause symptoms and overall well-being.

AMH (Anti-Müllerian Hormone)

Reflects ovarian reserve; indicates how far along you are in perimenopause
AMH is produced by ovarian follicles and declines with age and advancing perimenopause. AMH level correlates with ovarian reserve and can predict whether you are early, middle, or late in the perimenopause transition.
Target Early perimenopause: >2.0 ng/mL. Late: <0.3 ng/mL
Suggested Action Plan

AMH cannot be modified, but your result informs expectations. If AMH is still high, your perimenopause may be lengthy; plan hormone management accordingly. If very low, menopause is approaching soon.

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AMH (Anti-Müllerian Hormone) Guide
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Estradiol (Serum) Guide
Estrogen Dominance
Progesterone Guide
Menstrual Irregularities

Getting Started

1
Get Comprehensive Perimenopause Testing

Do not rely on symptom assessment alone. Test FSH, estradiol, progesterone, testosterone, and thyroid. Your specific hormonal pattern guides treatment. Testing at two points in the cycle (if you still have regular cycles) provides the most actionable information.

2
Identify Your Specific Hormonal Imbalance

Are your symptoms driven by low progesterone, fluctuating estradiol, thyroid decline, or a combination? Your test results pinpoint exactly which hormones need support and guide targeted therapy.

3
Consider Bioidentical Hormone Therapy

Bioidentical hormones (not synthetic ones like Premarin) match your natural hormones and are well-tolerated at physiologic doses. A functional medicine or integrative gynecologist can guide dosing based on your blood tests. Retest every 2-3 months during dose optimization.

4
Add Targeted Supplementation

Maca, red clover, black cohosh, and sage extract have research support for perimenopause symptoms. Magnesium helps sleep and mood. Omega-3 fatty acids reduce inflammation. Supplement choices should align with your specific biomarker pattern.

5
Retest and Adjust Every 2-3 Months

Perimenopause is dynamic; your hormonal needs change over time. Retest biomarkers every 2-3 months during the first year and annually after that. Adjust hormone doses based on symptoms and blood work, not just symptoms alone.

Why I built this guide.

"Perimenopause is manageable when you understand your specific hormonal pattern. Testing is the first step."

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