The science of fertility: Hormones, inflammation, and what you can control | Dr Natalie Crawford

Jan 26, 2026

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Fertility is not just about timing ovulation. In this episode, Dr Natalie Crawford explains how sleep, stress, insulin resistance, diet, toxins, supplements, and lifestyle choices influence egg and sperm quality, miscarriage risk, and fertility outcomes.

We cover fertility myths, evidence-based nutrition, supplements that matter, and when medical treatments like IVF or egg freezing make sense.

What We Cover

Sleep, inflammation, and hormone signalling
Insulin resistance and reproductive health
Strength training, stress, and metabolic resilience
Fertility nutrition and soy myths
Supplements that support fertility
Sex, ovulation timing, and common misconceptions
Fertility treatments and realistic expectations

A practical, compassionate, and science-driven conversation for anyone planning a pregnancy or struggling to conceive.

You can learn more from Dr Natalie Crawford by preordering her book The Fertility Formula at nataliecrawfordmd.com/book. You can also follow her on Instagram for ongoing fertility education, and listen to her podcast As a Woman.

Intro (00:00)
How Personal Loss Changed Medical Practice (03:34)
Infertility, Isolation, and the Power of Support Systems (11:32)
Fertility Is Not Luck: How Empowered Choices Shape Outcomes (16:03)
Common Fertility Myths and Misconceptions (21:31)
Sperm Health, Lifestyle, and Testosterone Risks (32:59)
Chronic Inflammation and Its Impact on Reproductive Health (42:50)
Egg Quality vs Age: What Really Drives Infertility (50:55)
Hidden Signs of Chronic Inflammation You Shouldn’t Ignore (01:01:22)
Tracking Your Menstrual Cycle as a Vital Health Sign (01:10:34)
Birth Control and Fertility Awareness (01:19:17)
Lifestyle Changes That Can Improve Natural Fertility (01:28:33)
Why Sleep Is Critical for Hormones, Fertility, and Metabolic Health (01:34:13)
Muscle Mass, Insulin Resistance, and Fertility Health (01:43:48)
How Food Influences Inflammation (01:53:33)
Supplements That Support Fertility and Egg Quality (02:05:56)
Fertility Supplement Red Flags (02:15:55)
Everyday Behavioral Toxins That Harm Fertility (02:29:46)
Common Fertility Myths Explained (02:36:19)
When to Consider Medical Interventions for Infertility (02:42:43)

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Simon Hill, MSc, BSc (Hons)

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