Abstract: A contraceptive device and method of contraception as well as a method of making the contraceptive device are described. Native collagen form of fibrillar protein is comminuted and homogenized in an acid environment; noncollagenous material is removed and residual collagen is mixed with water the pH of the resulting slurry is adjusted to 4.5 to 5.0 by the addition of acetic acid; gluteraldehyde is then added and the slurry poured into molds and frozen at approximately -10.degree. centigrade for approximately 20 hours. The frozen mass is then thawed, washed, and immersed in a wash of pH 8 to 9 for approximately 2 hours at 20.degree. centigrade. Sufficient reducing agent is added to the wash to create excess reducing equivalents. The sponge is then immersed in a buffer solution of pH 4 to 5 for a time sufficient to equilibrate to uniform pH. The sponge formed by the above method is then moistened and self-administered in the upper vault of the vagina proximal to the cervix.

Abstract: Method for making a collagen sponge including the following steps. Native collagen form of fibrillar protein is comminuted and homogenized in an acid environment; noncollagenous material is removed and residual collagen is mixed with water the pH of the resulting slurry is adjusted to 4.5 to 5.0 by the addition of acetic acid; gluteraldehyde is then added and the slurry poured into molds and frozen at approximately -10.degree. centigrade for approximately 20 hours. The frozen mass is then thawed, washed, and immersed in a wash of pH 8 to 9 for approximately 2 hours at 20.degree. centigrade. Sufficient reducing agent is added to the wash to create excess reducing equivalents. The sponge is then immersed in a buffer solution of pH 4 to 5 for a time sufficient to equilibrate to uniform pH. The sponge formed by the above method is then moistended and self-administered in the upper vault of the vagina proximal to the cervix. The sponge is then retained for a desired period, usually several days to one month.