text: It's true that briefs can cause a lack of active sperm.\nNot that every man who wears briefs is going to be infertile. \nBut what one wears is really a matter of comfort. Some men find brief too restrictive and other men find boxers too loose, becoming twisted and allows their genitals to rub causing irritation and discomfort.  It's really a matter of how you are built (hung) and what you find to be comfortable for you.\nI used to wear boxers most of my early life and then changed to briefs as I got older I found briefs more comfortable for me.