The Menstrual Cycle DECODED: Fertility, PCOS, and the New Science of Hormones

Pre-Order The Forever Strong PLAYBOOK and receive exclusive bonuses: https://drgabriellelyon.com/playbook/

Want ad-free episodes, exclusives and access to community Q&As? Subscribe to Forever Strong Insider: https://foreverstrong.supercast.com

In this episode, Dr. Gabrielle Lyon sits down with Dr. Heidi van den Brink; one of the only scientists in the world studying the ovarian transition from fertility to menopause. Together, they unpack what textbooks and wellness influencers often miss: the biology behind how your ovaries, uterus, metabolism, and nutrition interact across every stage of a woman’s life.

Dr. Heidi reveals the never-before-seen dynamics of the ovarian cycle, how follicles develop in “waves,” and what really happens during the menopause transition. They discuss how undernutrition, obesity, and metabolic health shape reproductive hormones; why early menarche and delayed ovulation matter for long-term health; and the surprising connection between your gut microbiome, bile acids, and fertility.

If you’ve ever been told to “balance your hormones” with seed cycling, apps, or supplements, this episode separates myths from mechanisms. It’s a masterclass in understanding the science of your hormones and how to truly support reproductive health through every decade of life.

Chapter Markers

0:00 - Can You Get Pregnant While on Your Period?

1:21 - Intro to Dr. Heidi & Ovarian Cycle Research

3:39 - The Uterine Cycle vs. The Ovarian Cycle

6:19 - Follicle Waves: The Hidden Drama in Your Ovaries

10:38 - Novel Discovery: Follicle Waves in the Luteal Phase

12:00 - Why One Follicle is Selected for Ovulation

13:17 - Does Nutrition Affect Ovarian Function?

14:48 - The Variation in Menstrual Cycles (It's Not Always 28 Days)

17:23 - The Impact of Obesity on the Ovarian Cycle

18:11 - The Problem of Luteal Phase Defects & Fertility

24:52 - Ovarian Morphology as a Bio-Marker of Health

26:54 - How Undernutrition Affects Ovarian Health

31:56 - The Metabolic Tipping Point of PCOS (Polycystic Ovary Syndrome)

33:26 - The Myth of the "String of Pearls" Ovary

35:25 - The Menopause Transition & Rogue Follicles

39:04 - Can We Predict Menopause by Scanning Ovaries?

45:59 - Early Menarche (First Period) and Long-Term Disease Risk

48:33 - The Surprising Link Between Puberty Timing and Environment

52:28 - The Role of Leptin in Reproductive Health

55:50 - Debunking the Myth: Can Nutrition Cure PCOS?

59:07 - PCOS Diet Myths (Fruit, Timing, and Supplements)

1:04:40 - Fish Oil for Menstrual Cramps (Dysmenorrhea)

1:08:37 - Breakthrough: Bile Acid, The Gut Microbiome, and Ovulation

1:11:50 - Closing Remarks

Who is Heidi Vanden Brink:

Dr. Vanden Brink is a reproductive physiologist with over a decade of research in nutrition, metabolism, and female reproductive health. Her work focuses on how diet and metabolic conditions like obesity influence reproductive development during adolescence, with the goal of preventing disorders such as PCOS.

Find Heidi Vanden Brink at:

• Texas A&M University: https://nutrition.tamu.edu/people/vanden-brink-heidi/ • • Google Scholar: