Was that a panty girdle Marilyn wore in dress blowup scene?

In the film "The Seven Year Itch," Marilyn Monroe wore a specifically designed undergarment for the iconic dress blowup scene. While it wasn't a traditional panty girdle, it was a type of supportive undergarment that helped create the desired silhouette. The garment was crucial for achieving the film's aesthetic while maintaining Marilyn's signature style.