When it comes to fertility and fatherhood, we men tend to think we’re invincible. After all, George Clooney’s looking at twin babies in his mid-50s, isn’t he? Like George, I put off marriage until later in life.

I was nearly 40 years old when I first got hitched, and 42 when I unexpectedly found myself divorced. Three years later I remarried, and not long after the wedding, my 32-year-old wife and I were happily surprised to find out we were pregnant. I say “surprised” because at 45, I knew that fatherhood wasn’t a foregone conclusion for me.

Everyone has a biological clock, a man's sperm count and quality diminishes with age, along with his libido. (Sorry, guys. The truth hurts.) Worse, many studies link older fatherhood with such complications as lower fertility, higher miscarriage risk, and an increased likelihood of autism and bipolar disorder in the offspring.

As a chronic worrier, I’m more Woody Allen than George Clooney. So I’ve looked into these issues. After my divorce I even froze my sperm, something I now ardently advise every man in his 20s or 30s to consider if he can afford it.

Retrieving sperm is much cheaper and simpler than retrieving eggs: I went to a lab, entered a small room stocked with outdated porn magazines, did my business into a sample cup, washed my hands, and handed the goods over to a technician.

That’s it. Storage can be a little pricey ($475 a year at the California Cryobank, where I stored mine), but you can save by buying in bulk (ten years for $2,680). It’s a small price to pay for peace of mind. (Here’s what it’s like to donate sperm.)

When my wife and I started thinking about kids, I elected to go au naturel. If we ran into problems, I could always retrieve my spermcicles. Luckily, we conceived with sperm that was “fresh, not frozen.”

WHY YOU NEED STRONG SPERM

We’ve heard a lot about the fertility problems of older men and women, but what’s less publicized is the extent to which a man’s diet and health play a role, even when he’s young.

Women are consistently educated on smoking, alcohol, diet, vitamins, and exercise. Why aren’t men? A man’s habits prior to conception could have a profound impact on his progeny.

Researchers know that smoking, a bad diet, lack of exercise, and exposure to environmental toxins are all detrimental to a man’s fertility and in some cases may affect the health of offspring. 

The upside: There’s new hope that lifestyle changes and other modifications can improve male fertility. These revelations are rooted in a relatively new field of research known as epigenetics.

Epigenetics—a buzzword that’s emerged in the scientific community over the past decade—is the study of how gene expression can be modified through lifestyle changes. While DNA is essentially hardwired code in our cells, epigenetic factors provide the instructions for that code. Think of genes as hardware and epigenetics as firmware. Your environment and behavior can actually change those instructions over time. Some scientists have also suggested that we could pass on epigenetically modified DNA to our kids and even to generations beyond. The good news is that many of the harmful changes brought on by bad habits may also be reversed through positive behavior changes—a firmware update, if you will.

Now a California startup offers something called an “epigenetic sperm test” to help men figure out the interplay of sperm and fertility.

SPERM TESTING 2.0

Tucked away in a craftsman-style bungalow in Pasadena, California, is the home of Episona, an epigenetics data company. Its $495 test, called Seed, could soon replace the common semen analysis in the diagnosis of fertility problems. It could also be used to predict the child’s risk of autism, schizophrenia, and other neurological disorders.

First Episona sends its testing kit to your address, packaged in a snazzy box. After you return your samples to its lab, technicians identify epigenetic abnormalities in genes associated with infertility.

At 44, with silvering hair and beard, Alan Horsager, Ph.D., Episona’s president and CEO, might have been a prime candidate for Episona’s technology had he not just had his second child. He did perform several epigenetic analyses of his own sperm prior to conception, more for his curiosity than anything else. Fortunately, he said, his analysis showed some “age-related stuff,” but nothing that put him in the infertile camp.

THE PROMISE OF SPERM EPIGENETICS

Here’s why all this matters: If you modify your behavior, you may change the DNA you pass down your family tree. When obese men had their epigenetic profiles assessed one week before gastric bypass surgery, one week after, and one year after, the researchers found shifts in regions important for neurodevelopment and metabolism.

Research also suggests that smoking-related defects in a man’s epigenetic profile can start to mend after he quits. Still more research found that three months of sprint interval training improved “sperm DNA methylation,” or the ways genes turn on and off. Changes were seen in genes involved in fetal organ development and even Parkinson’s risk.

Not everyone is convinced that Seed is ready for prime time. Nicholas Staropoli, who runs the nonprofit Epigenetics Literacy Project, thinks that even though Episona’s science is good, the data to support actionable conclusions about male fertility may not be there yet.

“We still don’t know a lot about how and even if the environment is driving these changes,” he says. But even though more studies are needed, he concedes that the test might have some use. “In vitro fertilization is expensive,” he says, “so a little piece of information to point you toward or away from IVF can be helpful.”

Episona is building a database to track how sperm epigenetics relates to fertility and other problems. In fact, Seed’s consent form points out that the research is ongoing.

The results of my Seed test showed some slight abnormalities in genomic regions associated with male infertility; this is fairly typical for my age, according to Dr. Horsager. Since my wife was already 20 weeks pregnant at that point, I didn’t worry.

While science appraises the long-term impact of Seed and epigenetic sperm evaluation, what’s clear is that your general health may be more critical to fertility and healthy offspring than we once thought.

The beauty of sperm health is that it can be improved—sometimes quickly—with lifestyle changes. “I can’t say to a woman, ‘Wait two months and your eggs will be better,’” said Aimee Eyvazzadeh, M.D., a Bay Area fertility specialist. “But I can say that to a guy about his sperm.”