What is a contraceptive sponge?
The contraceptive sponge, also known as the vaginal sponge contraceptive, is a round piece of white plastic foam that is moistened and inserted into the vagina before sex. It is 5 cm wide, has a dimple on the side that is inserted into the vagina, and a woven polyester loop on the other side to facilitate removal.
You can insert it up to 24 hours before sex, and each sponge can only be used once (1).
How does the contraceptive sponge work?
The sponge prevents pregnancy in two ways:
– It keeps sperm from getting into your uterus by blocking your cervix. The concave dimple on one side is fitted over the cervix to provide a physical barrier that prevents sperm from reaching the cervix.
– It continuously releases spermicide that kills sperm.
What does the contraceptive sponge look like?
How effective is the contraceptive sponge?
The effectiveness of a contraceptive sponge is dependent on how you use it. The risk of getting pregnant increases when the sponge is not used during every sex act.
The sponge is not the most effective method, especially if you have already had a child. With common use, only 76 to 88 of every 100 individuals will manage to prevent pregnancy.
For women who have not given birth, the failure rate is 16% with common use and 9% with perfect use. This means that with common use it is 84% effective while with perfect use it is 91% effective at preventing pregnancy.
For women who have already had children, the failure rate is higher at 32% with common use and 20% when used perfectly. This means that with common use it is 68% effective while with perfect use it is 80% effective at preventing pregnancy (2).
Although it is categorized as one of the least effect effective methods (even less effective than a diaphragm), the effectiveness of the contraceptive sponge increases when it is used in combination with a condom (3).
