On April 1 1983 the US Food and Drug Administration (FDA) approved a disposable vaginal sponge of soft polyurethane foam saturated with 1 gm of nonoxynol-9 as a nonprescription contraceptive offering 2 improvements over products already available: ability to leave in place up to 24 hours and no need for additional application of spermicide for repeated acts of intercourse. Clinical tests show the sponge to be comparable in effectiveness to other vaginal methods including the diaphragm. Although no major medical complications have been detected in studies of the sponge thus far concern over the possibility of its causing toxic shock syndrome led the FDA to require package labeling recommending that the product not be used during menstruation. The sponge was developed by the V.L.I. Corporation of California and will be marketed for about $1 under the brand name "Today." The sponge must be moistened with water before insertion to activate the spermicide and is believed to prevent conception by releasing the spermicide over 24 hours blocking the cervix to some extent and absorbing sperm. The sponge has undergone 5 years of clinical testing in the US and abroad and is the 1st nonprescription contraceptive to go through the safety and efficacy tests required for prescription drugs and devices. Controlled comparative tests conducted by the International Fertility Research Program began in 1979 in volunteers aged 18-40 who were randomly assigned to the sponge or another vaginal method. Available results are based on 1582 sponge users and 1579 controls. The data reviewed by the FDA advisory committee were based on 720 sponge users and a similar number of diaphragm users in the US segment. The 12-month pregnancy rates from the US trials were 15.8/100 women for the sponge and 11.6/100 women with the diaphragm not a statistically significant difference. The US data suggest that about 4% of users will develop allergic reactions such as itching irritation and rash.