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

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Jan 26, 2026

Dr Natalie Crawford, board-certified OBGYN and reproductive endocrinologist who turned personal loss into patient-focused care. She discusses how sleep, inflammation, insulin resistance, and strength training shape egg and sperm health. Nutrition, key supplements, toxin avoidance, and realistic use of IVF or egg freezing are covered in practical, science-forward terms.

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ANECDOTE

Personal Fertility Turning Point

Natalie Crawford described her four early pregnancy losses and being told to ‘just do IVF’ before she investigated lifestyle factors.
She changed diet, reduced inflammation, and later conceived without IVF, which shifted her clinical approach.

INSIGHT

Inflammation As A Central Driver

Chronic inflammation repeatedly appeared across disparate fertility research topics and likely drives many reproductive problems.
Reducing inflammatory burden can improve egg and sperm quality and fertility outcomes.

ADVICE

Question Self-Styled Hormone Experts

Beware unqualified 'hormone experts' and avoid hormone treatments without proper reproductive endocrinology context.
Never start exogenous testosterone if you may want children; it suppresses sperm and can cause long-term azoospermia.

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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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