Women’s underwear often has a small mystery: the extra piece of fabric in the crotch, known as a gusset. For years, people wondered if it was meant to “secretly hold tampons or lipstick” or add comfort.

On social media, one user asked: “I’ve always wondered why underwear has these holes???” Another dismissed theories, saying it wasn’t just for “reinforcement or some rubbish.”

The truth? The gusset is mainly for hygiene. One person explained: “The extra piece of fabric is called a gusset, and it’s there to reinforce the crotch area. It makes the piece more durable and stops moisture from seeping through.”

According to Cheeky Wipes, it helps keep you cool, prevents sweating, and “allows your vulva to breathe.” Underwear brand Leonisa adds: “The panty gusset serves several purposes… it prolongs the life of the underwear and helps catch discharge, sweat and other things, keeping you cool and dry.”

Mystery solved—the gusset is about comfort, durability, and hygiene.