An intravaginal contraceptive diaphragm made of collagen sponge: new old principle

This study presents a theoretical background for a new intravaginal contraceptive. A highly resilient and liquid-absorbent collagen sponge in the form of a cup is self-administered in the upper vault of the vagina, where it is retained for several days to form a mechanical barrier against sperm. The high fluid-binding capacity contributes to the trapping and immobilization of sperm within the sponge. Other methods enhancing the retention and spermicidal effect of the sponge are discussed. Clinical testing of the sponge is in progress.