The contraceptive sponge, which contains spermicide (a sperm-killing ingredient), is worn inside the vagina. It was once a popular form of contraception in the United States. It went off the market temporarily but become available once again in 2005. The sponge is available over the counter without a prescription.

Depending on the brand, the sponge can be inserted 12 to 24 hours before sexual intercourse and must be left in place for at least six hours afterward.

The sponge is about 90 percent effective in preventing pregnancy when used alone, and up to 98 percent effective when used together with a latex condom.

Advantages

• Because it is inserted ahead of time, the sponge allows intercourse to occur spontaneously. Once inserted, the sponge provides protection for 24 hours no matter how frequently the sexual act is repeated.
• The spermicide helps to decrease (but does not entirely prevent) the spread of sexually transmitted diseases.

Disadvantages

• The contraceptive sponge needs to be inserted before sexual intercourse and left in position for at least six hours afterward.
• Forgetting to use the sponge and not using it correctly are the most common reasons for failure, resulting in an unplanned pregnancy.
• About 4 percent of sponge users develop allergic reactions, and about 8 percent experience vaginal dryness or irritation. Some women may find the sponge difficult to remove.