Topic hub

Women’s Health & Hormones

Hormones, perimenopause, and the labs every woman should actually be tracking.

Women's health has been chronically under-studied and under-treated — most research was done in men, and symptoms like fatigue, brain fog, and disrupted sleep are still too often dismissed as "normal." Functional medicine takes a different stance: these symptoms are signals, usually traceable to hormones, metabolism, and nutrient status that standard care never measures.

This hub covers the hormonal arc of a woman's life — from optimizing cycles and fertility, through the turbulence of perimenopause, into the longevity window of menopause and beyond. It also covers the diagnostics that make the invisible visible: the estrogen, thyroid, iron, and metabolic markers that explain how you actually feel.

Written and reviewed by Robin Berzin, MD — Columbia-trained physician and founder of Parsley Health.

Common questions

Women’s Health & Hormones, answered

When does perimenopause start?

Perimenopause usually begins in the early-to-mid 40s but can start in the late 30s. It's the 4–10 year transition before menopause, when hormones fluctuate widely — often causing symptoms years before periods actually stop.

Is hormone therapy safe?

For most healthy women who start within about 10 years of menopause, current evidence supports that the benefits of hormone therapy — for symptoms, bone, and possibly brain and heart — outweigh the risks. The right choice is individual and worth discussing with a clinician.

Why are my labs "normal" but I still feel exhausted?

Standard reference ranges are wide and built around disease thresholds, not optimal function. Fatigue often traces to low-normal ferritin, suboptimal thyroid, low vitamin D or B12, or blood-sugar swings — all easy to miss on a basic panel.

Can estrogen support longevity?

Estrogen does more than regulate cycles — it supports bone, brain, cardiovascular, and metabolic health. Emerging research frames timely estrogen therapy as a potential longevity tool for women, not just a symptom treatment.

What labs should every woman track?

Beyond a basic panel: thyroid (TSH, free T3/T4, antibodies), ferritin, vitamin D, B12, fasting insulin and glucose, a lipid panel with ApoB, hs-CRP, and sex hormones timed to your cycle or menopausal status.

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Everything on Women’s Health & Hormones

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Vaginal Estrogen: Prevention, Not Last Resort editorial cut-paper collage illustration Women’s Health & Hormones

Vaginal Estrogen: Prevention, Not Last Resort

April 15, 2026

GLP-1s and Libido: What the Research Shows editorial cut-paper collage illustration Women’s Health & Hormones

GLP-1s and Libido: What the Research Shows

April 7, 2026

Normal Labs but Still Tired? 7 Root Causes editorial cut-paper collage illustration Women’s Health & Hormones

Normal Labs but Still Tired? 7 Root Causes

March 31, 2026

Bone Loss, Inflammation & Gut Health: The Missing Link editorial cut-paper collage illustration Women’s Health & Hormones

Bone Loss, Inflammation & Gut Health: The Missing Link

March 24, 2026

ADHD in Women: How Hormones Affect Focus and Diagnosis editorial cut-paper collage illustration Women’s Health & Hormones

ADHD in Women: How Hormones Affect Focus and Diagnosis

March 6, 2026

Why GLP-1s Underperform Without Estrogen editorial cut-paper collage illustration Women’s Health & Hormones

Why GLP-1s Underperform Without Estrogen

February 26, 2026

The Cortisol Reset Every Woman Needs editorial cut-paper collage illustration Women’s Health & Hormones

The Cortisol Reset Every Woman Needs

December 9, 2025

Testosterone Therapy Is Trending—But Is It Right For You? editorial cut-paper collage illustration Women’s Health & Hormones

Testosterone Therapy Is Trending—But Is It Right For You?

October 28, 2025

4 fasting for women strategies to optimize longevity editorial cut-paper collage illustration Women’s Health & Hormones

4 fasting for women strategies to optimize longevity

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My inside/outside skincare protocol editorial cut-paper collage illustration Women’s Health & Hormones

My inside/outside skincare protocol

August 5, 2025

Your bone density blueprint editorial cut-paper collage illustration Women’s Health & Hormones

Your bone density blueprint

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Why everyone 30+ needs a DEXA scan editorial cut-paper collage illustration Women’s Health & Hormones

Why everyone 30+ needs a DEXA scan

July 15, 2025

Why so many women are using creatine (including me) editorial cut-paper collage illustration Women’s Health & Hormones

Why so many women are using creatine (including me)

July 8, 2025

My cervical cancer scare editorial cut-paper collage illustration Women’s Health & Hormones

My cervical cancer scare

April 16, 2025

MTHFR mutations can cause anxiety, fatigue and fertility issues. You likely have one. editorial cut-paper collage illustration Fertility & Parenting

MTHFR mutations can cause anxiety, fatigue and fertility issues. You likely have one.

March 5, 2025

What is your vaginal microbiome telling you? editorial cut-paper collage illustration Women’s Health & Hormones

What is your vaginal microbiome telling you?

September 18, 2024

Brain, bones, booty: 3 things to take care of before you reach menopause.  editorial cut-paper collage illustration Women’s Health & Hormones

Brain, bones, booty: 3 things to take care of before you reach menopause. 

May 15, 2024

How to achieve optimal hormone balance, regardless of age editorial cut-paper collage illustration Women’s Health & Hormones

How to achieve optimal hormone balance, regardless of age

March 6, 2024

It’s raining men(opause) editorial cut-paper collage illustration Women’s Health & Hormones

It’s raining men(opause)

February 23, 2024