The sponge, a disk-shaped polyurethane foam device containing the spermicide
nonoxynol-9, is inserted into the vagina to cover the cervix. It acts as a barrier
but also holds spermicide (nonoxynol-9) up against the cervix. The sponge is
attached to a polyester loop for removal. The sponge protects for
up to 24 hours and for multiple acts of intercourse within this time. It should
be left in place for at least six hours after intercourse but should be removed
no more than 30 hours after insertion because of the risk, though low, of toxic
shock syndrome.

Although the product has been approved by the FDA, since 1983, as a safe and
effective over-the-counter device, production problems led its manufacturer
to voluntarily remove it from the U.S. market early in 1995. Another
company now owns the rights to the sponge and plans to market it at a cost of
approximately $2.50 per sponge (similar to the female condom). The company
plans to address complaints that removal was often difficult with the previous
product and the numerous reports of allergic reactions. A recent FDA Advisory
committee recommended reworking the sponge's labeling to warn women of the sponge's
risk of toxic shock syndrome -- to warn women not to keep the sponge inserted
for more than 30 hours and to feature an "allergy alert" against nonoxynol-9
and the sulfite contained in the sponge's spermicide. It is unclear whether
the recent reports of nonoxynol-9's association with increased risk of HIV will
affect this product launch, although at least one professional association is
calling for the product to be banned as a result. A broad range of women's
and reproductive health groups urged that the product return to the market as
soon as possible as another contraceptive option for the appropriate couples.

The sponge is less effective than other contraceptives, such as hormonal implants
or injections, birth control pills, male condoms, and the IUD, but had a higher
rate of pregnancy protection than spermicides alone. According to the FDA, use
of the sponge had the same one-year pregnancy rate as a diaphragm, cervical
cap, and female condom: approximately one in 10 women became pregnant
during their first year of correctly using the sponge. When used incorrectly,
pregnancy resulted in one in seven women during the first year. The sponge
promises better convenience, more control by women, and lower cost.