Men, if you're trying to help your partner conceive a child and also interested in tilting the odds in your favor as best you can, this might prove helpful. Possibly. That's according to researchers studying the relative temperature of sperm.
Among their main findings: men who wear boxer shorts have a 17 percent higher sperm count, and a 33 percent higher moving sperm count, than those who wear tighter briefs.
The reason, it's believed, is that there's an inverse relationship between scrotal-area temperature and sperm production, or as the study's authors write, "Elevated scrotal temperatures are known to adversely affect testicular function." What's not exactly known is why this is the case.
The controlled study, which was published online last week in the journal Human Reproduction, included data collected from 656 men seeking infertility treatment between the years 2000 and 2017, 53 percent of whom reported wearing boxers. The remainder wore various kinds of more restrictive underwear. Subjects fell between the ages of 18 and 56 years old. The median age was 35.5 years and body mass index (BMI) was 26.3 kg/m2.
Blood tests were conducted to measure testosterone levels and other hormones, and researchers controlled for several factors: race, age, BMI, smoking, and sauna and hot-bath usage. Not only were higher sperm counts found for boxer-wearers, but 25 percent in that group also had higher sperm concentrations.
While the study provided some insight, among the limitations was that it "only included men from couples seeking fertility treatment," and thus the "results may not be generalizable to men from the general population."
Another was that the data was self-reported via questionnaire, which always introduces some uncertainty into the research where, the authors wrote, "measurement error and misclassification of the exposure (type of underwear worn) is a concern." But they added that while "we are unaware of studies evaluating the validity of self-reported type of underwear worn, we have no reason to believe this behavior would be incorrectly reported by men."
Aside from scientific curiosity, the impetus for such a study is most likely male interest, specifically whether a connection exists between the choice of garment and sperm production. Research in this area goes back decades, with these authors citing studies dating to 1990 (Sanger and Friman). And yet, while the results are not clear-cut by any means, some additional insight into this area cannot hurt. So if you're looking to boost your fertility chances, however imprecise they may be, this simple switch, of course, carries no risk and is easy to make.