Deb Schwarz assumed that she was entitled to know her parents' medical histories, even though, under Pennsylvania law, she knew she couldn't get their names.

Like many adoptees, she was naive.

It took months for the agency that handled her adoption 36 years ago to dig her file out of the archives -- and only seconds for her to see that the information was worthless.

``Both your parents,'' the agency divulged, ``were in their mid-20s and were considered American.''

But what really outraged Schwarz, and turned the San Francisco marketing research consultant into a national crusader for open adoption records, was what she discovered after a private investigator located her mother in a Harrisburg nursing home.

Her mother is dying of breast cancer, a disease that Schwarz has learned is so prevalent in her family tree that she has decided to be tested for the breast-cancer gene.

``Adult adoptees deserve their medical information and heritage. We should not have to grovel, pay excessive amounts of money or go underground to get it,'' Schwarz declared in a recent letter to Pennsylvania legislators.

The revolution in medical genetics is having a profound effect on adoption. Adoptees, birth parents and adoptive parents alike are recognizing that adoptees need to know their risk for heart disease, cancer, depression and countless other genetically linked problems so that they can take steps to stay healthy.

Under pressure from adoption reform advocates, many adoption agencies have begun to collect detailed medical, psychological and social histories from birth parents on everything from migraines to musical aptitudes.

In December, Pennsylvania enacted a law that requires that birth parents be given forms so they can voluntarily update their medical histories while remaining anonymous. Similar laws have been proposed in other states.

But such reforms will not help adoptees like Schwarz, born before many common diseases were known to have a genetic component. They are in a bind: The best way to learn what may lurk in their genes is to ask their birth parents, yet that flies in the face of laws that seal birth records.

``There was a time when an adoptee could say, `I'm happy in my life and I have no need to look beyond that,' '' said Nancy Newman, a Bryn Mawr lawyer who founded the Pennsylvania Adoption Legislation Coalition. ``But now, because of what we know about hereditary disease, no matter how emotionally secure a person is with being adopted, there's still a question -- and it could be a life-threatening one.''

Daniel Wauters, 27, of Quincy, Calif., sometimes wondered whether he would live long enough to trace the roots of his cancer. A hereditary disorder called von Hippel-Lindau disease, it causes tumors on the eyes, kidneys, brain, spinal cord and other organs.

He and his adoptive mother, Joy Kerkhoff, waged an 11-year battle, which climaxed in court, to see his original birth certificate with his birth parents' names. During that time, Wauters went blind in one eye and endured many surgeries.

In September, he was finally reunited with his blood relatives. He learned that his mother had died of the disease and that his family had been struggling with it for generations. But he also gained hope.

``When I was diagnosed, I was made to believe it was more terminal and rare than it is,'' Wauters said. ``But my uncle is in his 60s. If I just monitor everything, I can live that long.''

Wauters is angry that secrecy prevails, even in the face of dire illness. He believes most birth parents are happy to be found. ``During the process of contacting my relatives, some were wary . . but upon meeting me, there was no denying me,'' Wauters said. ``My birth father was so elated, he was crying.''

Opponents of open records -- the Catholic Church, many bar associations and an adoption-agency lobbying organization called the National Council on Adoption -- argue that birth parents were promised confidentiality.

``To change the law now, many years later . . . would be unfair to these birth parents who justifiably relied on their protected right to remain anonymous,'' said Cynthia M. Jacob, president of the New Jersey State Bar Association.

Anti-abortion activists contend that eliminating confidentiality would prompt women to seek abortions instead of adoptions.

Pennsylvania had open records from 1978 to 1984 because of an opinion by the state attorney general. There was no surge in abortion rates or outcry from birth parents. The loophole was closed after persistent lobbying by the Pennsylvania Catholic Conference and anti-abortion forces.

The secrecy that shrouds adoption is a relic of the 1920s, says E. Wayne Carp, a history professor at Pacific Lutheran University in Tacoma, Wash.

Then, the stigma of ``illegitimacy'' induced most unwed mothers to surrender their babies, but finding adoptive homes was difficult. Not only did babies' birth certificates reveal their socially embarrassing beginnings, but the babies were up against eugenicists' pseudoscientific claims that unwed mothers were ``feebleminded.''

As a remedy, child-welfare reformers proposed sealing birth certificates at the time of adoption and issuing amended ones -- listing only the infant's new name and new parents. By 1948, most states had embraced that system.

Today, many unwed mothers-to-be, from Madonna to inner-city teenagers, make no apologies. And the scarcity of healthy white infants has spawned a new adoption process so mainstream that it recently became the stuff of the TV show Coach: An unwed pregnant woman meets with couples desperate for a baby and then makes a selection.

Nonetheless, only three states -- Alaska, Kansas and Hawaii -- allow adoptees, when they turn 18, to see their original birth certificates. Legislation that would give adoptees access in many more states, including Pennsylvania and New Jersey, has languished year after year.

Such a law was to have taken effect in Tennessee on July 1, but opponents -- an adoption agency, an unidentified adoptive parent and an unidentified birth parent -- obtained a temporary restraining order.

Internet adoption mailing lists buzz with stories of adoptees who believe this secrecy is denying them vital genetic information.

Schwarz, who began worrying about her genetic heritage when she and her husband decided to have a child, has collected examples:

[ * ] ``I . . . was shocked to hear my medical background when my birth mother found me,'' a woman wrote. ``My birth father had colon cancer when he was 40. I have always had bowel problems but never thought of cancer. Now I am checked yearly for signs. I also have had problems with my sugar levels. Found out my birth mother is a juvenile diabetic. . . . She told the agency everything she knew, but they never told my adoptive parents.''

[ * ] A woman who hasn't found her birth mother and is afraid of uterine cancer wrote, ``My gynecologist believes she may have used the hormone DES because . . . he has been concerned about abnormal cells.''

[ * ] A 25-year-old adoptee whose chronic depression went undiagnosed for years recently learned that her birth mother had committed suicide and that many relatives suffer from depression. ``I always blamed [ my adoptive family ] for everything. If we had the medical information, we would have known what to do sooner,'' she wrote.

Forewarned is forearmed, asserted Cleveland adoptee Georgianne Wiersch, 39. Twelve years ago, her birth mother told her she was at risk for adult-onset diabetes, which can damage the heart and kidneys if it goes undetected.

Wiersch became vigilant and was diagnosed six years ago.

``I controlled it with diet and exercise for five years, and now I'm on oral medication,'' she said. ``But I still have no'' organ damage.

While few states give adoptees access to birth parents' names, many have indirect contact systems.

Twenty-three states, including Pennsylvania and New Jersey, allow adoptees to try to reach birth parents through an intermediary -- an adoption agency, a state agency or a court.

Pennsylvania and New Jersey also have registries through which birth parents and adoptees can consent to a reunion. Opponents of open records say such registries are a good compromise.

But open-records proponents say intermediaries and registries are inefficient and often ineffective.

Pennsylvania's 15-year-old mutual-consent registry, for example, receives dozens of inquiries each month from adoptees and birth parents. But the registry conducts no active searches and is not well-known, so it facilitates only about five reunions each year.

``The problem is, if you have somebody stepping in the middle, you take away people's rights'' to know, said Bradford Jones, a lawyer and president of the Adoption Forum in Philadelphia.

Many adoptive and birth parents, as well as adoptees, bristle at the presumption that they are incapable of meeting without buffers.

``The more I talk about it, the crazier I think people's attitudes toward adoption are,'' said Jane Nast, an adoptive mother from North Jersey and legislative director of the American Adoption Congress. ``I said to one legislator, `Why don't you just open the records and let us make our own interpersonal messes?' ''

Adoptees acknowledge that many of them yearn for a chance to ask their parents, ``Why did you give me up?''

But their emotional needs are matched -- or even eclipsed -- by medical needs to know.

`Maybe I could meet my birth mother and have a decent relationship with her, but that's not what I'm looking for,'' said adoptee Michael Koziel, 39, of North Jersey, who has suffered kidney damage as a result of undiagnosed high blood pressure that may run in his family. ``I have a void. And I have two children. They deserve to know where they came from genetically.''

Giving adoptees access to records is no guarantee that they will find their parents, as Penny McGill knows.

McGill, 33, obtained her original birth certificate because she lives in Kansas, an open-records state. But after 15 years, she has found only her father.

McGill wants to know the roots of the rare congenital defect that caused both her sons to be born without soft spots on their skulls. The problem was surgically corrected in both boys, but her older son suffered brain damage before the condition was diagnosed.

McGill favors creating repositories for genetic and medical information that adoptees could get access to.

``For many of us, that's all we need,'' she said.

But for many adoptees, that's more than they will ever get.

Said Newman, the founder of the Pennsylvania Adoption Legislation Coalition: ``You've got this whole lost generation that can't get information. That's a very frustrating thing.''