The Fertility Test Most Men Are Never Offered | Dr Michael Eisenberg and Dr Natalie Crawford

2026-08-10

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About one in seven couples are unable to conceive after a year of trying, and roughly half of those cases involve a male contribution. Yet in a quarter to a third of them, the man is never properly evaluated. In this episode I sit down with Dr Michael Eisenberg, a urologist and Director of Male Reproductive Health at Stanford University, and Dr Natalie Crawford, a reproductive endocrinologist and co-founder of Fora Fertility in Austin, Texas. This is the comprehensive male fertility resource I went looking for and couldn't find, and I have a...

This is the comprehensive male fertility resource I went looking for and couldn't find, and I have a personal stake in it. What surprised me most is that sperm health appears to be about much more than conception. It tracks with metabolic health, immune health, pregnancy outcomes, and in one Danish cohort, with age of death decades later.

What We Cover

What a semen analysis measures, and why ejaculating normally tells you nothing
Semen quality as a sixth vital sign, and the Danish study linking it to lifespan
Testosterone therapy, why it functions as a contraceptive, and how long recovery takes
Whether sperm counts are really declining, and the likely drivers
Cannabis, alcohol, heat, cycling, sleep, and body weight
Total motile sperm count, DNA fragmentation, and what to ask your lab for
Paternal age, sperm freezing, and timing your decisions

Sperm turn over roughly every three months, which makes this one of the most movable metrics in health. Whichever stage of life you're at, this conversation is worth your time.

To connect with Dr Michael Eisenberg, find him on Instagram or LinkedIn. To connect with Dr Natalie Crawford, you can find her book The Fertility Formula at nataliecrawfordmd.com/book, listen to her podcast As a Woman, or follow her on Instagram, TikTok, YouTube, and LinkedIn.

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Simon Hill, MSc, BSc (Hons)