The vaginal sling is designed to replicate the function of the "hammock-like" pelvic floor muscles and connective tissues that naturally support the urethra. When these tissues are weakened—often due to childbirth, aging, or hormonal changes—the urethra drops during physical strain, preventing it from closing properly.

The sling acts as a permanent artificial ligament. It is placed under the mid-portion of the urethra. When abdominal pressure increases (during a sneeze, for instance), the urethra is pushed against the stable "backstop" of the sling, compressing the tube and maintaining a watertight seal. This restores the natural mechanical valve system of the bladder without requiring the patient to actively engage their pelvic muscles.