The contraceptive sponge is a non-hormonal, over-the-counter birth control method. This small, soft, disposable device is constructed from polyurethane foam and is pre-treated with a spermicide, typically Nonoxynol-9 (N-9). The sponge works in a dual fashion: it acts as a physical barrier and continuously releases a chemical agent.
The physical barrier function involves the sponge being placed deep inside the vagina to cover the cervix, which is the opening to the uterus. The spermicide, Nonoxynol-9, is a surfactant that chemically disrupts the sperm cell membranes, causing them to rupture and die. This combined mechanical and chemical action prevents sperm from reaching and fertilizing an egg.
Preparing for Insertion
Before handling the sponge, thoroughly wash your hands with soap and water. Take the sponge out of its packaging and prepare it for activation by moistening it with about two tablespoons of clean water. Gently squeeze the sponge until it feels wet and slightly sudsy, which ensures the spermicide is activated.
Once activated, fold the sides of the sponge upward, away from the small fabric loop, making it long and narrow for easier insertion. The indentation in the center of the sponge should be facing up, toward the cervix, and the removal loop should face down. Find a comfortable position, such as squatting or standing with one foot raised, similar to how one might insert a tampon.
Using your fingers, slide the folded sponge deep into the vagina, pushing it as far back as you can. The sponge will naturally expand and unfold once it is released, covering the cervix. You should then check the placement by sliding a finger around the edge to confirm that the cervix is fully covered.
Duration and Timing Rules
The contraceptive sponge offers continuous protection for a total duration of 24 hours once it has been correctly inserted. You have the flexibility to insert the sponge up to 24 hours before sexual intercourse. During this 24-hour period, you can engage in sexual activity multiple times without needing to replace the sponge.
Following the last act of intercourse, the sponge must remain in place for a minimum of six hours to ensure that all sperm are trapped and neutralized by the spermicide. Do not exceed a total wear time of 30 hours. Leaving the sponge in for longer significantly increases the risk of a rare but serious condition called Toxic Shock Syndrome (TSS).
Completing the Removal Process
Begin by thoroughly washing your hands with soap and water. Get into a comfortable position, such as sitting on the toilet or squatting, to make the process easier. Locate the small fabric loop used for removal.
Gently pull on the loop to slide the sponge out of the vagina. If the loop is difficult to reach, you can bear down with your vaginal muscles, similar to a bowel movement, which can help move the sponge closer to the opening. If you cannot locate the loop, you can grasp the sponge itself between your thumb and forefinger to pull it out.
Once the sponge is removed, inspect it to ensure it is fully intact. The used sponge must be immediately discarded into a trash receptacle. Never attempt to flush the sponge down the toilet, as it is not biodegradable and can cause plumbing issues.
Success Rates and Risks
The effectiveness of the contraceptive sponge varies depending on whether a woman has previously given birth. For women who have never had a vaginal delivery, the sponge is approximately 91% effective with perfect use. This effectiveness drops to about 86% with typical use.
For women who have previously given birth, the effectiveness is lower due to potential changes in the fit of the cervix, with a perfect-use rate of about 80% and a typical-use rate of 73%. The spermicide, Nonoxynol-9, can sometimes cause irritation or burning in the vagina or on a partner’s penis. This irritation can potentially increase the risk of contracting sexually transmitted infections (STIs), including HIV, by creating microscopic breaks in the vaginal lining.
A rare but serious risk associated with sponge use is Toxic Shock Syndrome (TSS), a bacterial infection. Women with a history of TSS or those who are sensitive or allergic to spermicide or polyurethane should not use the sponge. The sponge does not provide any protection against STIs, so combining it with a barrier method like a condom is advised for disease prevention.