Contraceptive sponge

The contraceptive sponge combines barrier and spermicidal methods to prevent conception. Three brands are marketed: Pharmatex, Protectaid and Today. Pharmatex is marketed in France and Quebec; Protectaid in Canada and Europe; and Today is available in the U.S.^[1]

The sponges are inserted vaginally prior to intercourse and must be placed over the cervix to be effective. To facilitate removal, Today has an elastic band across the sponge; Protectaid has two slots.

Sponges provide no protection from sexually transmitted diseases (STDs).

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Effectiveness

The manufacturer of the Today sponge reports effectiveness for prevention of pregnancy of 89% to 91% when used correctly and consistently. When packaging directions are not followed for every act of intercourse, effectiveness rates of 84% to 89% are reported.^[2] Other sources cite poorer effectiveness rates for women who have given birth - 74% during correct and consistent use, and 68% during typical use.^[3]

Studies of Protectaid have found effectiveness rates of 77% to 91%.^[4][5]

Studies of Pharmatex have found perfect use effectiveness rates of over 99% per year.^[6] Typical use of Pharmatex results in effectiveness of 81% per year.^[7]

Sponges may be used in conjunction with another method of birth control such as condoms to increase effectiveness.

Use

The Today sponge must be run under water until thoroughly wet before insertion.^[2] The Protectaid^[1] and Pharmatex^[7] sponges come ready to use.

Insertion of the sponge requires reaching the cervix and is generally performed by the woman. Intercourse can proceed when it is placed or hours afterwards. The sponge must be left in place for several hours after ejaculation in the vagina (Today and Protectaid recommend six hours, Pharmatex two).^[1]

All sponges must be removed within the time limits specified by the manufacturer - 24 hours for Today and Pharmatex and 18 for Protectaid.^[1]

History

The Today Sponge was introduced in the United States in 1983. The Pharmatex sponge was introduced in France and the Quebec province in Canada in 1984.^[8] The Protectaid sponge was introduced in Canada in 1996, and in Europe in 2000.^[1] All three brands are available outside their normal marketing areas through internet retailers.

The Today sponge was removed from the U.S. market in 1994 after problems were found at the factory where they were produced for Wyeth Pharmaceuticals. Wyeth stopped selling the sponge rather than upgrade its plant. In 1998, Allendale Pharmaceuticals scraped together money to buy the patents and the complex manufacturing equipment. Tough new FDA standards for manufacturing and record-keeping forced repeated delays (some users started calling it the "Real soon now sponge"), but the Today sponge was finally re-introduced in Canada in March 2003, and in the U.S. in September 2005. In January 2007, Allendale Pharmaceuticals was acquired by Synova Healthcare, Inc, based in Media, PA. Synova plans a multimedia advertising campaign for the sponge. Synova chairman and CEO Stephen E. King cited current controversies over the long-term health effects of hormonal contraception, saying they created favorable conditions for expanding the sponge's market share.^[9]

Spermicide

Sponges are a physical barrier, trapping sperm and preventing their passage through the cervix into the female reproductive system. The spermicide is an important component of pregnancy prevention; each brand offers a different formula.

The Today sponge contains 1,000 milligrams (mg) of nonoxynol-9.^[10] Protectaid contains 5,000 mg of the F-5 gel, with three active ingredients (6.25 mg of nonoxynol-9, 6.25 mg of benzalkonium chloride, and 25 mg of sodium cholate).^[7] Pharmatex contains 60 mg of benzalkonium chloride.^[1]

Side effects

The contraceptive sponge has a few risks, including tearing, yeast infection, and allergic reactions from the spermicide. Improper use, such as leaving the sponge in too long, can result in toxic shock syndrome.

The sponges are not effective in preventing sexually transmitted diseases. The spermicide nonoxynol-9 in fact increases the risk.

In Popular Culture

Shortly after they were taken off the U.S. market, the sponge was featured in an episode of the sitcom Seinfeld titled "The Sponge". In the episode, the character Elaine Benes conserves her remaining contraceptive sponges by refusing intercourse unless she is certain her partner is "sponge worthy".

See also

• Cervical cap
• Diaphragm (contraceptive)
• Lea's shield
• SILCS diaphragm