Spermicides and sponges Spermicides and sponges Spermicides and sponges are barrier contraceptives that work by killing sperm or providing a barrier between the male's sperm and the uterus. Both are available in most drugstores without a prescription.
Spermicides come in several different forms, including foams, creams, jellies, and suppositories.
Before intercourse, the spermicide must be inserted into the upper part of the vagina. It should be inserted usually no less than ten minutes prior to intercourse. The effectiveness of the spermicide generally lasts for no more than an hour, so another application of spermicide should be used if additional intercourse takes place. According to Planned Parenthood, its rate of effectiveness varies from seventy percent to ninety percent, depending on how much of the product is used, the timing of insertion, and how well the packaging instructions are followed. Spermicidal effectiveness is greatly increased when used with another barrier method such as a condom.