Think of sperm as a delivery system. The job isn’t just to reach the egg—it’s to deliver intact, healthy DNA that can support fertilization, embryo development, and a successful pregnancy. When DNA inside the sperm is damaged or broken (fragmented), it can still fertilize an egg, but the embryo is less likely to thrive.

Why does it matter?

Even when the semen analysis looks “normal,” high levels of sperm DNA fragmentation are linked to:

• Difficulty conceiving naturally
• Higher risk of failed IVF or IUI
• Recurrent miscarriage (this is the most common one we see)
• Unexplained infertility

This means the problem isn’t always about egg quality or ovulation—it can often be hidden sperm factors that simply aren’t being tested or a combination of the two.

What causes sperm DNA fragmentation?

The biggest culprit is oxidative stress—when there’s more free radical damage than the body can repair. But many other factors contribute:

• Paternal age
• Varicocele (enlarged veins in the scrotum)
• Infections and inflammation (including gut dysbiosis, which fuels systemic inflammation)
• Environmental exposures (plastics, pesticides, toxins, smoking, alcohol)
• Heat (hot tubs, saunas, even laptops on the lap)
• Poor sleep and chronic stress
• Mineral deficiencies—low levels of zinc, selenium, magnesium, and manganese make it harder for the body to repair DNA and protect against oxidative stress. Iron overload can also be a contributor to inflammation and DNA fragmentation.

It’s no wonder we’re seeing this more often in practice today—modern life brings a heavier load of stressors, exposures, and nutrient depletions than ever before.

Signs oxidative stress may be impacting sperm health:

• Frequent fatigue or burnout
• Chronic inflammation or pain
• Poor recovery after illness or exercise
• Recurring infections
• High exposure to toxins, smoke, or alcohol
• Digestive issues (a clue for gut-driven inflammation)

If these sound familiar, oxidative stress could be playing a role in fertility struggles.

The hopeful part

Here’s what I want you to remember: sperm regenerate every ~74 days. That means the choices made today can directly influence sperm health in just a few months. With the right support, we regularly see sperm DNA fragmentation improve—leading to healthier pregnancies and better outcomes for couples who once felt stuck.

Sperm health is one of the topics we cover on our functional fertility mini podcast series that you can listen to here.

​reminder: i’m currently accepting people into my Nurture Your Fertility program. you can learn more here about the program and fill out an application!