Want To Grow Your Family? This Is the Time of Year When Men Are Most Fertile

For decades, the conversation about pregnancy timing has largely been had around a woman's reproductive cycle. From the best time of month to try to conceive (during ovulation) to a woman's most fertile years (late teens to early thirties), experts and hopeful parents alike have spent a lot of time talking about female fertility.

However, it would appear we've all been missing a big chunk of information, since men and their sperm play a massive role in the fertilization process during conception.

So, when are men most fertile? Researchers have spent quite a bit of time analyzing sperm samples from a variety of men to figure out when they are most fertile, and the answers are actually kind of surprising. Unlike a woman's reproductive cycle, men don't appear to have monthly fertility fluctuation. Instead, their fertility seems to vary depending on the time of year.

Curious to know what that means? Keep reading as we explain when men are fertile, and what that means for reproduction.

Researchers from the University of Manchester studied semen from over 15,000 men worldwide, checking when sperm motility (AKA: the sperm's ability to swim to where it needs to go) is at its highest. According to Newsweek, they discovered that they were in their best shape during the summer months of June and July, making this a man's most fertile time of year.

Conversely, researchers say that the little swimmers had their lowest points in December and January.

These samples were taken as part of a study that used donations collected from 2018 to 2024 and included men aged 18 to 45.

Newsweek says these men were from very diverse geographic locations, including Denmark and Florida. Even with the extremes in climate and temperatures, researchers say their results held up across both locations. This leads them to believe that factors tied to the seasons — like daylight, physical activity, or colds — make a greater difference than temperature alone.

As you may know, those who are born with ovaries are born with all of the eggs they will ever have. As they get older, the number of eggs decreases, which lowers their fertility levels.

However, the genetic makeup of male biology is different, and men continue to produce new sperm each day. So, their fertility isn't quite as tied to the number of sperm they have at any given moment, but instead their ability to produce quality sperm that can get where they need to go.

According to the British Fertility Society, men don't typically begin to see a decline until between 40 to 45, which means they remain highly fertile until around that time.

Men can remain fertile until they are no longer producing sperm with optimal sperm motility. That being said, the British Fertility Society says that determining whether or not a man is fertile can't be determined strictly by whether or not he is able to ejaculate, since it's still possible to experience issues with infertility while producing semen.

However, there is really no cutoff date for me, since some men in their 80s have been known to still be able to father a child.