Clinical acceptability, use-patterns and use-effectiveness of the vaginal contraceptive sponge and Neo Sampoon tablets--an international multi-center randomized clinical trial.

This paper describes the results from a randomized clinical trial comparing the Collatex vaginal contraceptive sponge (a predecessor of the Today sponge) and Neo Sampoon foaming vaginal contraceptive tablets; the trial was conducted from 1979 to 1983 in four centers located in three countries (two in Yugoslavia and one each in Taiwan and Bangladesh). The sponge was associated with more insertion and retention problems than the tablet, especially in the two Asian centers. More Neo Sampoon users complained of a burning or stinging sensation. This complaint, however, seemed to be well-tolerated and was not a frequent reason for irregular use and/or discontinuation of use of the tablets. Clinically significant medical complications were rarely reported for either method. Sponge users were more likely to report irregular use than tablet users, primarily due to inconvenience of use. Rates of discontinuation at six months of use were also consistently higher among sponge users than Neo Sampoon users in the four centers. Life-table pregnancy rates at 12 months of use ranged from 3.8 to 18.2 per 100 sponge users and 6.2 to 29.9 per 100 Neo Sampoon users, based on data from the two Yugoslavian centers and the Taiwan center (data from the Bangladesh center were excluded from analysis of pregnancy rates). Practical implications of these findings are discussed.