VLI Officials Defend Contraceptive Sponge After Critical Studies

Officials at VLI Corp. responded angrily Friday to reports that the company’s contraceptive sponge is far less effective than claimed for women who have already borne children.

Recent studies conducted by North Carolina and New Jersey researchers contend that the Irvine company’s Today contraceptive sponge failed in 28% of women who had previously given birth. A brochure packaged with the sponges says there is a failure rate of 9% to 15%.

“When you look at the clinical trial results, which included women who had had children and who hadn’t, there is no evidence to indicate that the Today sponge has higher failure rates with women who have had children,” said Mary George, VLI vice president for marketing. But one of the new studies, conducted by Susan McIntyre and James Higgins of Family Health International, a nonprofit research organization in Research Triangle Park, N.C., found that Today’s failure rate among 1,454 women was 28.3% among those with children, compared with 13.9% among childless women.

Princeton University’s Office of Population Research demographers Kathyrn Kost and James Trussell conducted a review of three sets of studies and found that the sponges failed to prevent pregnancy in 28% of women with children, compared with 18% of childless women.

Some researchers suggest that the vaginal sponges are less effective in some women than others because the size of the cervix and vagina varies while the sponge is available in only one size.

The researchers believe the spermicidal sponges are less effective in blocking and killing sperm in women who have given birth, because childbirth enlarges the cervix and vagina.

But George contends that such a theory is false because “the Today sponge’s primary mode of action is releasing the spermicide . . . so the size does not become a factor in preventing pregnancy,” she said.

Details of the studies were reported late Friday, after the close of stock trading. VLI common shares closed at $4.875 for the day, unchanged from Thursday’s close.