Fertility · Mar 18, 2026 · 6 min read
Luteal Phase Defect: When Your Cycle's Second Half Falls Short
Discover what a luteal phase defect is and how low progesterone can affect your cycle, fertility, and PMS. Learn when to test and how it's treated.
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Read clear, research-based articles about hormones, symptoms, and lab tests. Use them to prepare questions for your next visit.
Featured · Hormones
What your luteal phase is actually trying to tell you
The second half of your cycle is the part most women never get tested during. This biomarker-level guide explains why most doctors read it wrong.
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Hormones · Mar 18, 2026 · 5 min read
DHEA-S: The Hormone That May Be Behind Acne, Energy, and Aging
DHEA-S, a key adrenal hormone, may be linked to energy, skin health, aging, and PCOS. See what high or low levels may mean and which lab tests to request.
Hormones · Mar 18, 2026 · 6 min read
Testosterone in Women: Why It Matters More Than You Think
Testosterone is not just a male hormone. Learn why it matters for women's energy, libido, muscle strength, and bone density, and how to test it.
Hormones · Mar 18, 2026 · 6 min read
Progesterone Deficiency: May Be the Most Underdiagnosed Hormone Imbalance
Progesterone deficiency may be one of the most overlooked hormone imbalances in women. Learn its link to anxiety, insomnia, and PMS, and how it's tested.
Hormones · Mar 17, 2026 · 3 min read
Cortisol at 7am: what a morning cortisol can tell you about your entire year
The cortisol awakening response can spike in the 30 to 45 minutes after you wake. Learn what it may say about burnout, and when and how it's measured.
Hormones · Mar 15, 2026 · 7 min read
How Hormones Can Affect Sleep: The Estrogen-Progesterone-Cortisol Connection
Your hormones may be why you can't sleep. Learn how estrogen, progesterone, and cortisol can shape sleep, and which lab tests can identify the root cause.
Thyroid · Mar 14, 2026 · 3 min read
The five labs every perimenopausal woman should run
A normal TSH can mask years of subclinical thyroid dysfunction in perimenopause. Learn the five labs that can show the full thyroid cascade.
Hormones · Mar 10, 2026 · 7 min read
Endocrine Disruptors and Your Hormones: What Xenoestrogens Can Do to Your Body
Xenoestrogens in plastics, cosmetics, and food packaging can disrupt your hormones. Learn what they are and which lab tests can detect their impact.
Hormones · Mar 5, 2026 · 8 min read
Hormonal Weight Gain: Why You Cannot Lose Weight and What Lab Tests Can Show
Hormonal weight gain can be driven by insulin resistance, cortisol, thyroid dysfunction, and estrogen imbalance. Learn which labs can uncover the cause.
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