In 1984, 28-year-old Sara Wood of Los Angeles went to a doctor's office to have liquid silicone injected into her fallopian tubes as part of a new sterilization method that was being studied at the time.

Today, Sara Wood-Strauss contends that the procedure caused her years of disabling pain and produced autoimmune symptoms. Her case, which has come to the attention of the Food and Drug Administration, is the most recent episode in an ongoing controversy about the health effects of silicone in the body. Some of Wood-Strauss's reported symptoms mimic the immune system problems reported in recent years by some women who had silicone gel breast implants, which have now been banned by the FDA.

Silicone is used in a huge variety of medical products ranging from liquid lubricants in syringes to solid artificial joints in limbs. Eighty-four different categories of medical products contain silicone, according to the FDA. For years, the medical community has relied on the material for its versatility. But the breast implant controversy has put silicone under new scrutiny.

"Years ago if you asked most people, they would say, 'Silicone is inert. It's perfectly safe to put in the body,' " said Elizabeth D. Jacobson, deputy director of the FDA's Center for De- vices and Radiological Health. "That picture is changing."

A suit filed in Los Angeles in June by Sara Wood-Strauss and her husband Peter Strauss against the doctor who inserted the silicone and the manufacturer charges that silicone leaked into Wood-Strauss's blood and internal organs. They contend that the silicone led to intense pain, bowel problems and autoimmune disease, in which the body attacks its own tissue. Wood-Strauss's current complaints include difficulty excreting, general fatigue, skin rashes and joint pain. She said she is disabled and was forced to close her chiropractic practice because of her health problems.

"I was very healthy before the silicone was put in my body and now I'm not," said Wood-Strauss.

Approximately 1,700 women volunteers in the United States underwent the same silicone sterilization procedure as Wood-Strauss between about 1978 and 1987, according to the FDA, which approved a clinical trial of the device. According to documents provided by the FDA, the liquid silicone was pumped into the fallopian tubes and then solidified almost immediately into a rubbery solid. By blocking the fallopian tubes, the plugs prevented pregnancy. A major advantage of the method, its proponents said, was that it provided a nonsurgical form of sterilization, thus avoiding general anesthesia and potential complications of surgery.

Another "hidden attraction" was that it might be reversible, said Gabriel Bialy, acting deputy director of the Center for Population Research at the National Institutes of Health (NIH). NIH funded early studies of the device in the 1970s. In experiments with rabbits, Bialy said, researchers managed to pull out the plugs, much like removing the stopper from a sink, and restored the animals' fertility.

The American manufacturer, Ovabloc Inc., never completed studies required by the FDA for marketing the product, including long-term safety studies in animals to determine whether the device causes tumors. The company is no longer in business in the United States, the FDA said. The product is currently produced by Alphatron, a Dutch company located in Rotterdam, and is sold in Europe.

Vicki G. Hufnagel, a Burbank, Calif., doctor who performed surgery on Wood-Strauss earlier this year and brought her case to the attention of the FDA, said she found silicone throughout Wood-Strauss's pelvic area that looked like "threads, dots of spray paint." She thinks the liquid silicone leaked out of the fallopian tubes at the time it was pumped in. "It's like spilling hot plastic all through your body, so your body is no longer soft and pliable." Hufnagel has reported two additional cases of women with silicone plugs who she said also suffered auto immune problems.

FDA officials said they know of no other cases of problems with the silicone plugs. On July 7, FDA officials wrote to the 12 medical centers that oversaw the clinical studies of Ovabloc, informing them of Hufnagel's cases and requesting that they report any adverse effects in women patients who received the Ovabloc plugs, including autoimmune responses or evidence of tumors.

Steven C. Gambardella, the Woodland Hills, Calif., attorney representing Wood-Strauss, said that the scientists and doctors who tested the silicone plugs should have been aware of experiments indicating that silicone stimulated immune activity in laboratory animals. Pointing to studies from the 1970s that have recently been publicized in connection with the breast implant litigation, he called the clinical trial of the plugs "an experiment conceived against a terrible background of evidence that silicone can and does severely impact the human organ system."

But the doctor who inserted the plugs in Wood-Strauss said he was unaware of any such studies when he performed the procedure on 30 women. "In the early '80s when we were doing these clinical trials ... there was absolutely no reason to suspect that there were any problems at all," said Charles M. March, professor of obstetrics and gynecology at the University of Southern California School of Medicine.

March said that until the suit was filed, he was not aware that Wood-Strauss had complaints related to the plugs. He added that his other patients "are absolutely without complaints."

March also expressed skepticism that there is any relationship between symptoms attributed to breast implant patients and the silicone plugs, since the plugs solidify. By contrast, scientific interest in recent years has focused on the silicone gel inside the breast implant sac. The jamlike gel is considered more likely to leak into the body than solid silicone.

FDA officials too have expressed less concern about silicone solids than about liquids or gels, because the solids' tightly linked molecular chains contain fewer leachable molecules. The difference in risk between the solid silicone and the gel "is similar to comparing getting on a country road with few cars and getting into heavy traffic," said Lee Schroeder of the FDA's Office of Science and Technology at a June 2 FDA hearing.

More than two years ago, the FDA removed silicone-gel-filled breast implants from the market, following hundreds of reports from women complaining of autoimmune diseases and other problems. The FDA is also considering regulating saline breast implants, which are salt water encased in a sac made of rubber and silicone.

However, FDA's investigation of the connection between silicone and autoimmune disease has come under growing criticism from the medical community. A study of 749 Mayo Clinic patients published in the New England Journal of Medicine June 16 found that women with breast implants were no more likely to suffer autoimmune diseases like rheumatoid arthritis than women without implants. The study, one of three recent large epidemiological studies to find no harm from the implants, was accompanied by an editorial calling the FDA's removal of the implants from the market "overly paternalistic and unnecessarily alarming."

"Scientifically, we can't say there's a link {between silicone and autoimmune disease} because the link hasn't been demonstrated," said Jacobson of the FDA. "We know we have case reports {of symptoms from women with implants}, but we don't know if it's definitely linked."

Nevertheless, FDA officials point to two animal studies in their possession that would explain theoretically why silicone could cause problems. One dating from 1974 by scientists from Dow Corning Corp., formerly the leading manufacturer of silicone gel breast implants, and another published in 1993, indicate that silicone stimulates an immune response. In April, FDA released another Dow study conducted in 1975 suggesting that the silicone breast implant could do more immune damage than the company acknowledged two years ago, when the controversy was sparked.

"Only recently has the scientific literature contained well-controlled studies in animals suggesting immunological aspects of silicone," said John J. Langone, chief of FDA's Molecular Biology Branch. "We're doing some studies in our own laboratories that we think will shine some light on the potential adverse effects."

Numerous medical devices are made from silicone-containing polymers

UROGENITAL

* Oviductal plugs

* Testes

* Penile prosthesis

* Urethral stent

ARTIFICIAL ORGANS

* Skin

* Heart, pacemakers, intra-aortic balloons, pumps, valves

* Lungs

JOINTS

* Wrist

* Toe

* Finger

* Hip (impact cuff)

* Shinbone cuff

* Synovial (knee) fluids

COSMETIC

* Toupee adhesive

* Contact lenses

* Chin

* Ear frame

* Gluteal pads

* Breast implants