When the copper intrauterine device returns to the American market next year, most of the women who use it will first be asked by their doctors to sign a detailed consent form.

The consent form is seen by proponents as a way of informing consumers about IUD risks while also reducing the manufacturer's liability to lawsuits that have helped drive some IUDs off the market.

The new contraceptive IUD, called the T 380A or the Copper T, has been available abroad for several years and is expected to reach the domestic market early in 1988 following final approval of its labeling by the Food and Drug Administration. It was developed by the Population Council, an international nonprofit family planning organization, and will be distributed in the United States by GynoMed Pharmaceutical Co., a small 3-year-old company in Somerville, N.J.

While the new IUD itself is not especially remarkable, the use of a consent form in its distribution is. "It's a fairly isolated example now, but in my opinion it's the way of the future," said Roderick Mackenzie, GynoMed chairman.

The form, now "in about its ninth draft," will be submitted to the FDA next month, Mackenzie said.

In urging doctors to ask women to sign the consent form before using the T 380A, GynoMed is following the lead of Alza Corp., manufacturer of the only IUD now available in this country. The GynoMed consent form is modeled on the seven-page form that Alza has distributed with its non-copper Progestasert IUD since August 1986.

By signing the Alza form, a woman acknowledges that she has read it "in its entirety and discussed its contents with my doctor or nurse practitioner" who has "answered all my questions and advised me of the risks and benefits associated with the use of the Progestasert system, with other forms of contraception and with no form of contraception."

The form also acknowledges that an IUD user "may experience serious medical problems {that} could lead to surgery, sterility, permanent hormonal imbalance or death."

Such a consent form is highly unusual in the pharmaceutical industry.

"We're in an industry that has taken the magic bullet approach and emphasized the great benefits of their products," said Peter F. Carpenter, executive vice president of Alza. "Those benefits exist, but no pharmaceutical product achieves its benefits without certain associated risks."

The consent form is designed to let both doctors and patients know that no drug is a "magic bullet without some potential side effects," he said. "Our motivation in doing this is to make sure the woman is well informed -- not to cover our backside," Carpenter said. "Of course, it has the added effect of reducing our liability."

Most drug companies maintain that it is primarily the role of the physician and the pharmacist to tell patients about an approved drug's potential medical risks, but Carpenter said "that does not happen with anywhere near the frequency with which it should."

An IUD is a small piece of molded plastic with a string attached, which is inserted into the uterus through the cervix. Some IUDs contain copper or the female hormone progesterone. How they work is not completely understood, but IUDs are thought to interfere with the growth of the fertilized egg by reacting with the uterine lining.

IUDs are an effective form of birth control but have a checkered history because of numerous problems they can cause -- including increased menstrual bleeding and pain and pelvic infections -- and the particular disaster of the Dalkon Shield.

The Dalkon Shield, first sold in the late 1960s, caused serious infections and infertility in many users because of a defect and had to be withdrawn from the market in 1974. The Dalkon Shield's problems prompted thousands of lawsuits against its manufacturer, A.H. Robins Co., and several congressional investigations that led to FDA regulation of medical devices.

Alza's Carpenter said it's too early to tell if the new consent form was a factor in the recent "general downward trend" in the number of product liability lawsuits against IUDs.

Ortho Pharmaceutical Co. stopped selling its Lippes Loop IUD in September 1985, and G.D. Searle & Co. discontinued its Cu-7 and Tatum-T IUDs in January 1986. Both companies cited economic reasons, and Searle in particular attributed its move to the rising cost of fighting product liability lawsuits and the unavailability of product liability insurance for such products.

Since its first IUD went on the market in 1974, 15 IUD-related lawsuits against Searle reached the trial stage, Searle spokeswoman Kay Bruno said. Of those, Searle won 13 and lost two. The two judgments against Searle totaled about $300,000.

But the cost of fighting other lawsuits was even higher. In 1985, the last year before its two IUDs were withdrawn from the market, Searle spent more than $1.5 million to defend itself successfully against four product liability lawsuits, Bruno said.

Since then, the only IUD sold in the U.S. has been Alza's hormone-releasing Progestasert, which has relatively low sales of between 50,000 and 75,000 a year.

Use of IUDs by American women peaked at 5 percent in the early 1970s and has declined steadily since 1974, when Robins ended sales of the defective Dalkon Shield. Among American women using contraceptives, 2 percent used an IUD last year, according to industry estimates.

Dr. Sidney Wolfe, director of Public Citizen's Health Research Group and a frequent critic of the pharmaceutical industry, praised the Alza-GynoMed consent form as a welcome alternative to the "Madison Avenue approach" of boosting drug sales by accentuating the positive and downplaying possible side effects and risks.

"There's no question the informed consent approach will not sell as many products as the Madison Avenue approach," Wolfe said, "but the people who buy them will know what they're getting into.

"We're very pleased by these kinds of moves," Wolfe said. "On the other hand, we don't see drug companies rushing to follow suit."

"It's sort of a first," said Mark Grayson, a spokesman for the Pharmaceutical Manufacturers Association. But he said IUDs represented a "special category" because of the large number of lawsuits against them and predicted that the informed consent approach would not be adopted by companies for other FDA-approved products.

"It's a step in the right direction to inform women and physicians about the risks of IUDs," said Judy Norsigian, co-author of "The New Our Bodies, Ourselves," the Boston Women's Health Book Collective's health guide for women. "It may mean, unfortunately, that women won't have recourse to lawsuits if something goes wrong."

But if detailed consent forms force doctors and patients to understand, consider and weigh the benefits and risks of medical products, she said, the result would be healthy.

"People should not be taking risks they don't understand," she said.

Detailed consent forms are required for many types of surgery and experimental treatments but are rare for FDA-regulated drugs or devices such as IUDs.

"There's no doubt we'll see more of this," said Jaxon White, president of MEDMARC, a mutual insurance company that provides product liability insurance for about 400 manufacturers of medical devices. Product liability is "a primary consideration" in deciding to market a medical device, White said.

In designing its consent form, GynoMed borrowed liberally -- with Alza's permission -- from the consent form distributed with Alza's Progestasert IUD over the past year.

"You have to write it in such a way that the patient can't just say, 'Oh, I read it,' when in fact they really didn't spend the time necessary to understand it," said GynoMed's Mackenzie. The repeated initialings and the signature required at the end are aimed at ensuring that patients actually read the statement, paragraph by paragraph.

Mackenzie said it is "very difficult" to monitor actual use of the form by physicians. "We can't direct the practice of medicine; we can only recommend and support," he said.

"What you're trying to do is get rid of the allegation by the patient that she didn't know there were any risks," said George J. Annas, professor of health law at Boston University and chairman of the American Bar Association's science and technology section. "It's not easy, because most physicians don't talk to their patients very much," Annas said.

What distinguishes the IUD consent form from warning labels and printed inserts distributed with many prescription medicines is the requirement of the patient's and the doctor's signature. It is especially important for women to know the potential risks of an IUD, Annas said, because they could easily choose other methods of birth control.

"If ever there was a case for informed consent and telling patients what the risks are," he said, "it's something like the IUD."