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).
Studies of Protectaid have found effectiveness rates of 77% to 91%.
Studies of Pharmatex have found perfect use effectiveness rates of over 99% per year. Typical use of Pharmatex results in effectiveness of 81% per year. Sponges may be used in conjunction with another method of birth control such as condoms to increase effectiveness.
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).
All sponges must be removed within the time limits specified by the manufacturer - 24 hours for Today and Pharmatex and 18 for Protectaid.
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 bought the patents and the complex manufacturing equipment. 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 executed a multimedia advertising campaign for the sponge. Talking about their planned campaign, 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. In December 2007 Synova filed for bankruptcy reorganization. In 2008 the manufacturing rights to the Today sponge were purchased by Alvogen.
The Today sponge contains 1,000 milligrams (mg) of nonoxynol-9. 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). Pharmatex contains 60 mg of benzalkonium chloride.