Soaking Up Success: "Unbelieveable" is how biomedical engineer Bruce W. Vorhauer describes response to his contraceptive sponge, which won marketing approval last month from the Food and Drug Administration.

"Some of the mail is from people who say they want to hop on a plane and fly out to get it," says the 41-year-old president of VLI Corp. of Costa Mesa, Calif. "Half is from people who want to buy stock in the company and the rest want to work for us."

The nonprescription, disposable, spermicide-soaked sponges will be available in 11 western states in July and nationwide this fall for $1 each under the brand name "Today." Once inserted into the vagina, the sponge provides protection up to 24 hours, through repeated acts of coitus. Tests show it to be about 85 percent effective in preventing pregnancy--about the same as the diaphragm or spermicide alone, notes the FDA, but less than the 98 percent rate of the birth-control pill and the 95 percent rate of the IUD.

Unlike the sea sponges soaked in citrus juice used more than 3,000 years ago by Egyptian women to prevent pregnancy, "the sophisticated material we have today is very pure and very clean," says Vorhauer. The polyurethane is "similar to that used in artificial heart valves and arteries."

Vorhauer got the idea for the device in 1975 when employed by a hospital-supply manufacturer. "There was so much dissatisfaction with existing birth-control methods. I was amazed at how little new biomedical application had been done."

When his supervisors refused to pick up on the concept, he quit his job and tried several other manufacturers. When the sponge was met with still more rejections, he formed his own company.

"It's nice to be vindicated," admits Vorhauer, who--like "most of the men at my company"--has had a vasectomy.