Is there a consumer product anywhere that enjoys massive sales without benefit of saturation advertising? A product which, in fact, may not so much as be whispered on the airwaves and often may not be displayed on store shelves?

There is such a product, and it is, of course, the contraceptive.

While the entire notion of advertising birth-control devices is still raising the ulcer quotient on Madison Avenue and causing cast-iron TV network money men to blanch, along comes Cornell University's J. Mayone Stcos to argue that not only should there be contraception advertising but that it should be sexy to boot.

"If modern advertising has spent a half century infusing the subject of sex into areas where it does not belong," he argued in a recent paper, "family planning has spent the same amount of time busily eradicating it from a location it uniquely merits."

Stycos is director of Cornell's internation population program of graduate studies, and he argues that contraceptive information is so oblique and subtle around the world that a lot of people may not be getting the message: that contraceptives mean sex with no babies.

Any Madison Avenue type might see that right off as a good selling point: "an aid to family planning" is not much good for anyone with no intention of "planning a family" in the first place.

The whole notion, however, makes other birth-control advocates nervous. The subject of birth control makes entire sectors of society furious, and Stycos acknowledges that "the roof could fall in" if his proposal is converted into sexy ads for contraceptive products. The idea of any ads at all is controversial enough.

There have always been contraceptives, of course: Cleopatra was said to have used a gold marble. There have been sheaths made of goat bladders and pessaries of crocodile dung, and men of the Elizabethan era occasionally dipped their private parts in tar in the vain hope of avoiding offspring.

However, information about contraceptives has often been harder to get than the devices themselves. "The birth-control movement, which began as a liberal - even radical - sexual and feminine liberation movement, has desexualized itself in order to accommodate the conservative politics of communications," Stycos said.

From Margaret Sanger's advocacy of birth control as a way to free women to live and love as men do, the movement had to shift to social themes in order to get anybody to listen, Stycos argued. The talk turned from sexual freedom to prevention of crime and reduction of prostitution, ill health and unemployment.

Then it went to "improvement of the species" in arguing for contraception (mostly for other folks), and finally to "family planning" for the benefit of the kids and for the relief of an over-populated world. "Sexuality has been drummed out of the movement," Stycos said.

The result is the birth-control information is now offered in a "typically sterile, slightly prudish and somewhat dated tone which reassures the older generation but which alienates or amuses the young, he went on. "There is a distinct cultural lag."

There is controversy, however, not just over the tone of such information but over whether it ought to be offered at all. Here one gets into the entire issue os sex education and whether it encourages or discourages sexual activity, and then into the question of whether contraceptive advertising (or any advertising, for that matter) is a form of sex education.

Sexy advertising is occasionally blamed for what many regard as alarming rates of prenancy and promiscuity among the young.

One million abortions were performed last year in the United States, 325,000 of them on teen-agers, according to the Planned Parenthood Federation of America. A new study by the National Center for Health Statistics, a part of the Department of Health, Education and welfare, reports that one fifth of all births are unwanted at the time of conception, and Planned Parenthood says half of all out-of-wedlock babies are born to teen-agers.

In a February policy statement, Bishop James S. Rausch, general secretary of the U.S. Catholic Conference, argued that ads for conceptives would be "a gross violation of the rights of parents to guide the moral and social development of their children."

Other church groups disagree. The General Conference of the 10-million-member United Methodist Church last year supported "free flow of (contraceptive) information . . . through periodicals, radio, television and other advertising media."

The National Association of Broadcasters polled 210 religious, medical, fraternal, psychiatric and social service organizations in the last two yeats on whether they would approve contraceptive ads on television. The 55 groups who responded were divided evenly on the prospect.

So delicate is the issue that the NAB doesn't expect a decision before next spring on whether it will even sponsor test ads on selected member stations.

"You could kick up a lot of dust with the sort of thing (Stycos) is saying," said Tina Johnson, publications editor of Planned Parenthood. "Many parents or just adults in general will go along with (advertising) as it is, but if you put too much sex in it they'll balk at the whole idea."

A billboard campaign in New York City subways was expicit: "words to the effect that if you want sex but don't want babies, call this number. But what works in the New York sunways won't necessarily work elsewhere. You have to feel your way through this," she said.

Several birth-control workers dismissed fears that advertising contraceptives would foster promiscuity, saying sex is already pretty popular and explicit in other ads. Rodney Shaw, director of the Population Institute in Washington, noted that ads abound for products concerning "the rest of that area" - hemorrhoids, "jock itch," toilet paper, sanitary napkins, constipation and feminine deodorants.

"For the one thing that most affects our lives, television has abdicated its responsiblity," Shaw continued. The institute meets regularly with church groups on the taste level of proposed sales pitches, all of which are subtle so far, Shaw said.

One shown to a National Council of Churches committee featured a young couple romping through a field and then embracing tenderly to a fadeout, with the product name (Emco Foam), nothing else. "At the end, one of the committee members asked what it was they were selling," Shaw related.

Posters and billboards in Great Britain are similar. "They don't use the word contraceptive. They use the brand name and you're supposed to know what it is," said a British embassy spokesman.

Stycos insisted he has "no desire to step over the bounds of good taste either." Contraceptive ads would require millions of dollars in advance research and testing, he said, just like all the other ad campaigns that now use sex to sell everything.