When it comes to male fertility, it turns out that size does matter. But not the measurement that most men worry about. Size really matters when it comes to fertility, since a new study suggests that even infertile men are less gifted.
Having a shorter appendage was more common in men who were struggling to conceive than in those with other genital health problems. The research, which will be presented this week at the American Society for Reproductive Medicine conference in Colorado, is the first ever to link the length of the penis to fertility.
He found that on average men who were infertile were about a centimeter lower than their fertile counterparts. Those without reproductive problems had an average length of 13.4 cm while those of the infertile group were 12.5 cm.
He said underlying conditions that caused infertility, such as hormonal issues or problems in the testes, may also lead to a shorter penile length.
“This is the first study to identify an association between shorter penile length and male infertility,” he said.
The dimension in question is a measurement known as anogenital distance, or AGD. The shorter the AGD, the more likely a man was to have a low sperm count, a U.S. study has shown.
Men whose AGD is shorter than the median length – around two inches – have seven times the chance of being sub-fertile as those with a longer AGD, according to the study published on Friday in the journal Environmental Health Perspectives.
That distance, measured from the anus to the underside of the scrotum, is linked to male fertility, including semen volume and sperm count, the study found.
‘Sub-fertile’ means that a man has a sperm count of less than 20 million per millilitre. Past research has shown that men in this category have about half the chance of conceiving as do men with normal sperm counts.
According to study author Shanna Swan of the University of Rochester Medical Center in New York, the new finding offers the prospect of a relatively simple fertility screening test for men.
“It’s non-invasive and anybody can do it, and it’s not sensitive to the kinds of things that sperm count is sensitive to, like stress or whether you have a cold or whether it’s hot out,’ Swan said in a telephone interview with Reuters. If somebody’s got a short AGD, particularly if they have problems conceiving, I would say get to the infertility doctor, because the chances are good that something is wrong.”
But Dr Natan Bar-Chama, who heads the male reproductive medicine at Mount Sinai Hospital in New York, stressed that the study was the first of its kind in humans.
“Assessment of AGD as a routine evaluation of one’s fertility is premature,” Bar-Chama, who wasn’t involved in the study, told Reuters Heath.
To reach their conclusions, researchers measured the AGDs of 126 men born in or after 1988, a small but statistically significant sample, Swan said. The study did not address what might cause certain men to have short AGD measurements.