Handsome men may have better semen, a study suggests.
The good-looking men had healthier sperm
Researchers in Spain have found that men who are regarded as attractive by women are also more fertile.
Their sperm move faster and are generally healthier.
The study is the latest to suggest that good looks can be a pointer to good health.
In April, researchers in Australia found that men with chiselled jaws and classic masculine features are in better physical health than their less manly peers.
These and similar findings have led scientists to conclude that women who seek attractive male partners are, in fact, searching for the healthiest men, most able to father and provide for their children.
In this latest study, researchers at the University of Valencia took sperm samples from 66 men. They also took photographs of each of the men. A group of 66 women rated these men on their looks.
The researchers then randomly selected pictures of 12 men, who each had either good, normal or bad semen.
The study showed a link between the quality of semen in men and whether women found them attractive
Two more groups of women then rated these men on the basis of their looks.
The researchers found the men with the best quality semen were also ranked most attractive by each of the three groups of women.
Maria Sancho-Navarro, a researcher at the University of Valencia, said men were generally rated as being attractive if they had "symmetrical" faces.
"The women found that men with symmetrical faces were more attractive. These men had eyes, ears and nose that were more symmetrical than the other men," she told BBC News Online.
"The study showed a link between the quality of semen in men and whether women found them attractive."
She added: "Previous studies have shown that men who have symmetrical faces are healthier and they suffer fewer illnesses."
The study is published in the journal Evolution and Human Behavior.