Sperm 101

Everything you wanted to know about your swimmers. (And a number of things you didn’t know you wanted to.)

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The hard facts

Average age40

40 years ago, men had twice as much sperm as they do today.


Roughly half of all fertility issues are related to complications with male fertility.

1 in 8

The number of U.S. couples who have fertility issues.

The sample

There’s more to sperm health than count. Meet the sperm health indicators:

It’s in your hands

  • Quit the Cigs

    Plenty of evidence links cigarette smoking to negative effects on several important factors to your semen, from count to motility and beyond. Long story short? Men and women who smoke have decreased fertility.

  • Skip the Mary Jane

    While there is limited evidence evaluating the effects of marijuana on fertility, brand new research just demonstrated a link between miscarriages and fathers’ marijuana use.

  • Cut the Junk

    Junk food has its name for a reason. Many studies point to the fact that following a healthy diet is associated with better semen quality.

  • Sleep On It

    Get your eight hours! Late bedtimes and sleep deprivation impair your sperm health, weakening your fertility.



Fertility is only a women’s issue.

When it comes to fertility, it’s an equal playing field. In fact, of the 40–50% of couples who have trouble conceiving, “male factor” infertility is the cause.

If my sperm is “bad,” it’s all over.

It’s really just the start. Simple lifestyle changes like improving your diet or adding a few laps at the track are easy ways to begin improving your fertility.

You can have a healthy baby at any age or life stage, and only women need to worry about their age as it relates to childbearing.

Numbers don’t discriminate. While there are those random 90-something-year-olds getting women pregnant, researchers have linked “advanced paternal age” (defined as age 35+) with a plethora of health challenges.

So—should I switch to boxers?

Briefs won’t impact your sperm health long-term, but if you’re actively trying to conceive you should make the switch.

Sperm’s the future.

Semen is a window into men’s overall health; just as skin and teeth can reveal clues about your internal health, semen can as well. So the more we know about sperm as a health indicator, the more we can help collectively make strides in fertility, men’s health, and the health of our future generations. And that’s what Fellow is all about.

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