P&S Journal: Spring 1997, Vol.17, No.2
Ethics in Medicine: Fetal Diagnosis and Treatment
FOURTH IN A SERIES
By Devera Pine
|Photo by Jonathan Smith|
|Tamika Pressley and son, Anthony Ramos at 2 months of age. Anthony was born at 26 weeks.|
These tests, combined with new treatments, are allowing
doctors to detect birth defects with ever-increasing precision
and, in some cases, offer intrauterine treatment. But, like all
medical advances, the tests and treatments are accompanied by
Making the Diagnosis
Tests that screen for birth defects, though beneficial, also pose risks, says Dr. Kwame Anyane-Yeboa, associate professor of clinical pediatrics and director of clinical genetics. Chorionic villi sampling (CVS), for instance, can introduce infectious agents into the uterus, rupture the amniotic sack, or cause a miscarriage. The risk of such complications is approximately 1 percent. Amniocentesis has about a 1 in 200 risk of causing complications, and fetal blood sampling poses a complication rate of 1 percent to 3 percent. For this reason, the risk for the disorder being tested should be equal to or greater than the risk of the test, says Dr. Anyane-Yeboa.
Photo by Jonathan Smith|
Dr. Frank A. Manning
Photo by Jonathan Smith|
Dr. Lindsey Allan
"What goes into the decision-making process is complicated. There's tremendous stress, tremendous financial cost in raising a handicapped child," he says. "It's never straightforward."
A new range of treatments can now help babies with medical problems before birth. "In two decades, medicine has advanced remarkably in this area," says Dr. John M. Driscoll Jr., the Reuben S. Carpentier Professor and Chairman of Pediatrics. "There have been a lot of changes that give us the chance of influencing things that were previously hopeless."
For instance, the treatment of a blocked bladder in utero is now so successful that 80 percent of fetuses that are treated survive. Before the advent of such surgery, only about 2 percent survived, says Dr. Frank A. Manning, who in 1980 performed the world's first in utero surgery to relieve an obstructed bladder. Dr. Manning joined P&S in 1996 as the Virgil Damon Professor of Obstetrics and Gynecology and director of the division of maternal-fetal medicine and clinical assessment.
However, just because a treatment enables a baby to survive the full-term pregnancy does not necessarily make the treatment beneficial. Physicians are able to treat hydrocephalus, an excess accumulation of fluid in the brain, in utero with shunts and drains. Two-thirds of those treated in utero survive vs. the one-third that survive if the condition is untreated. But after birth, approximately 60 percent of the treated babies suffer from seizures, retardation, cortical blindness, and other serious abnormalities. As a result, in 1988 physicians declared a moratorium on that type of fetal surgery.
|This sonogram shows a hypoplastic (abnormally small) left ventricle in a fetus. The left ventricle (labeled LV) should be the same size as the right ventricle (RV). A hypoplastic left ventricle is one of the most common congenital heart defects. Most babies with this condition are given compassionate care and die within a week of birth. At P&S, a series of three surgeries now improves the chances of survival of a baby with this condition.|
"One of the absolute requirements in fetal medicines is that we follow up and report on how the children we treat do," says Dr. Manning. For instance, approximately 30 years of follow-up on the treatment of Rh disease has shown that treatment increases chances of survival to about 90 percent. "But that still means that in every 10th patient the baby is going to die."
No matter what the outlook for the baby, physicians have a clear ethical duty to correctly diagnose conditions and inform the parents, says Dr. Lindsey Allan, professor of pediatrics. "You work with the parents to try to make the correct decision. The difficulty is when you're not able to give a clear long-term outlook. But the parents must be told that too, even if you disturb them with your lack of certainty."
With some heart defects, for example, physicians may not be able to determine in advance how severe the defect will be. In these cases, the physician must walk a fine line between giving up hope too soon and fostering false hopes.
"Often, before parents have any children, they don't realize what it will mean to have a child with a severe heart defect," says Dr. Allan. "For instance, it may be much more difficult to leave the child with a caregiver and go back to work. It's difficult enough having children. But when you have a child with defects requiring multiple surgeries, parents may have to give up their lives for that."
|Photo by Jonathan Smith|
|Margaret Edward-Worrell and daughter, Kyla, at 32 weeks of age. Kyla was born at 26 weeks.|
These type of procedures generate ethical questions: Is it
right to "save" a baby, only to have him or her need a heart transplant
20 years down the line? If this type of procedure becomes more common,
will it exacerbate the shortage of hearts available for transplants?
If so, how do we allocate those hearts: Are these 20-year-olds more
"deserving" of a transplant than someone who is getting a transplant
at age 60? There are no easy answers.
Holding On: Ethical Dilemmas After Birth
The ethical dilemmas do not end when prenatal testing has normal outcomes. Some babies are born prematurely; others have so many problems their very survival is questionable. Approximately 10 percent of infants are born prematurely, and 1 percent of all infants have significant congenital malformations.
Fetuses as young as 22 weeks occasionally do survive, but they face an uncertain future. "You're never exactly sure how mature a baby in that age range is," says Dr. Karl F. Schulze, associate professor of clinical pediatrics and acting director of the newborn intensive care unit. The uncertainty makes it difficult to determine which babies should receive aggressive treatment and which should be given only compassionate care. "The stakes are high," says Dr. Schulze. "A baby could grow up to be a perfectly normal college graduate or so severely retarded that he or she needs lifelong custodial care."
Babies with an array of birth defects present the same difficulty. "You have to decide whether the congenital abnormalities can be corrected in a way that would allow the baby to function at an acceptable level," says Dr. Schulze. Often, physicians don't have a good precedent to follow, as each baby may have a unique combination of birth defects. "In general, if the brain is normal, we will respond with aggressive treatment to any array of physical deformities," says Dr. Schulze.
"The frustrating thing about ethical decision-making is that it requires such a sophisticated understanding of biology and medicine that it's often difficult for us to educate parents," he says. "For instance, both 22- and 25-week-old babies are just small babies in the eyes of parents. But the differences in the complications that might befall them are such that it takes a fairly sophisticated biologist to understand them." Generally, babies have a much better chance of survival at 25 weeks than they do at 22.
The decision to treat a premature baby--or not--cannot be made in a vacuum, Dr. Schulze points out. If there are other healthy children in the family, that may need to be taken into account, he says. And, sad to say, financial considerations are always lurking in the background: The average cost of treating a baby who weighs less than 1.5 pounds is about $250,000, and the hospital stay often exceeds 100 days. "Is this the proper allocation of our ever-diminishing health care dollars?" asks Dr. Schulze. Although insurance may cover much of the cost, parents may still be left with huge medical bills.
Then there is the situation in which a baby is born to a mother who is HIV-positive. The baby's HIV status may not be known until the baby is several months old. If that baby has congenital abnormalities, should aggressive treatment be the course?
"There's no wrong answer and no right answer, even if you treat the baby and he or she then dies four years later from AIDS," says Dr. Schulze. "One question that may be asked in these situations--and probably is not asked enough--is if this was your child or grandchild, what would you recommend?"
Society has not discussed the admittedly highly sensitive issue of whether age and weight limits should be set to determine which babies receive treatment and which are allowed to die, says Dr. Stephen Brown, co-director of the division of clinical genetics, assistant professor of obstetrics and gynecology, and director of the DNA diagnostic laboratory. "Babies born prematurely get an unbelievable amount of public resources spent on them. A baby born at 30 weeks costs society between one-quarter and one-half a million dollars. And large numbers of them will end up with a neurological impairment. At this point, the decision-making is technology-driven, and efforts to make decisions on moral and ethical grounds are so divisive that they are usually not discussed." At CPMC, parents are always included in the process of deciding whether a baby should be treated.
A less controversial way of addressing the problem, says Dr. Brown, would be to fund programs to prevent premature births. "There should be an all-out intense national effort to prevent premature births. It's a far bigger problem than AIDS. It doesn't get talked about, but it is."
The Big Picture
Despite all of medicine's advances--in genetic testing, prenatal diagnosis, and treatment--little headway has been made, from a statistical point of view, in preventing the majority of birth defects, notes Dr. Stephen Brown, co-director of the division of clinical genetics, assistant professor of obstetrics and gynecology, and director of the DNA diagnostic laboratory. "For a given individual, these advances can make all the difference in the world, but from a population or epidemiological point of view, we have not made major advances against preventing the majority of birth defects." Instead, he says, what has changed is American attitudes toward birth.
"Chromosome diagnosis only makes sense statistically with trisomy 21 (Down's syndrome). Virtually all other chromosome abnormalities are lethal," he says. Most cases of severe retardation in children today cannot be detected prenatally. "If you really found every chromosomal abnormality in all women, you could reduce the burden of severely mentally retarded children to society, but it would only constitute maybe 5 percent of severely retarded children."
Dr. Brown makes the same argument about sonograms, the use of which, he says, has not significantly affected the number of children born with defects. And intrauterine fetal treatments apply to so few fetuses that from an epidemiological point of view--from the view of the total population, not from the individual perspective, Dr. Brown stresses--they have little effect.
"The advances in technology have been the source of a lot of enthusiasm, but what has really changed in the last 20 years is attitudes toward pregnancy," he says. "The average prospective parents in 1997 think it's their right to have a perfect baby and that [physicians] can tell if they're going to have a perfect baby. But by and large, we cannot." One of the most difficult genetic counseling issues medical professionals face, he says, is getting people to understand that having a baby always entails the risk of birth defects and mental retardation.
Despite the difficulties and ethical problems that still remain, technology--and medicine's ability to diagnose and treat fetuses--continues to advance. What those advances will be or where they will take medical diagnosis and treatment is impossible to predict. The only constant is that the advances in treating fetuses will bring new, ever-changing ethical dilemmas.