You probably think that a guy who looks like Joe Manganiello or Jon Hamm could get you pregnant just by looking at you a little too long. And new research says that a guy’s face actually does contain clues about his swimmers—just not in the way you might think.
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The study published in the journal Evolutionary Biology looked at 50 Caucasian male students from the University of Valencia in Spain. These men had their semen analyzed, then their photos were rated for facial attractiveness (by other male and female participants) and facial masculinity (characterized by things like eye size, lower face height, cheekbone width, lip width, nostril width, and lower face area). Then the researchers tested whether any of these traits were associated with the quality of semen.Â
Interestingly, they found that facial attractiveness was positively associated with sperm quality. But they also found that men with more masculine features (like a wider face) had lower sperm quality than men without these features.
Why? The researchers aren’t entirely sure, but one theory is that having more masculine facial features coincides with increased testosterone. And according to the researchers, previous studies have found that high levels of testosterone could impair sperm production. So it turns out that super-buff guy at your gym that just oozes manliness may actually have lower-quality sperm, which may affect his ability to make a brood of beautiful babies. (Shame…)
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Obviously this doesn’t mean that your incredibly attractive guy is super-fertile or that the manly man your dating is actually impotent. Remember, this was just one small study on 50 men, but the results are definitely intriguing. For more concrete intel, check out these nine things you never knew about sperm.