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What Would You Do If Your Doctor Said Your Fetus Had a 1 in 6 Chance of Being Born With Down Syndrome?

Two families, faced with the results from rapidly advancing prenatal tests, grapple with the decision.

By Dr. Adam J. Wolfberg
February 15, 2009
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Liberally coating Sonia's abdomen with ultrasound gel so cold it made her shiver, Dr. Erika Peterson made precise arcs with the wand, playing the ultrasound beam over the fetal structures deep within Sonia's womb. The obstetrician's job that day was to see if she could detect any markers that might signal Down syndrome. Sonia, 40, and her 46-year-old husband, Dave, both software professionals, had come to Tufts Medical Center after the results from a set of blood tests and an earlier ultrasound had flagged Sonia as high risk for carrying a fetus with Down syndrome. Finally, after long minutes focused on the ultrasound screen, Peterson turned to the couple in the darkened ultrasound room. "Let's talk about markers."

She had seen what is known as echogenic bowel, which means that on ultrasound, the fetal intestines were too bright. Although this finding can be normal, it is seen at times in fetuses with Down syndrome, a condition characterized by an extra chromosome that results in mental retardation and often a host of medical problems. Peterson thought that the echogenic bowel, together with Sonia's high-risk test results, made it more likely, but not certain, that her fetus had Down syndrome. Without using a needle to obtain fetal cells and actually counting the chromosomes -- or waiting until her child was born -- there would be no way to know for sure.

Since 1983, when doctors noticed that alpha-fetoprotein was usually low in the blood of women who carried a fetus affected with Down syndrome, the search has been on for a test, or combination of tests, that would diagnose the syndrome early in a pregnancy. Women and their partners use this testing so that they can prepare to raise a child who will have profound medical, cognitive, and behavioral challenges, or so that they can end the pregnancy. The best tests now detect up to 95 percent of Down syndrome by combining results from blood tests in the first and second trimesters with an ultrasound examination in the first trimester, and obstetricians across the developed world are screening more of their patients than ever before. None of these tests, however, provide a definitive yes or no answer -- although blood tests that do are in development and may be available as soon as June.

In much of Europe, this increase in screening has coincided with a decrease in the number of babies born with Down syndrome, because many women, armed with this new information, have chosen to terminate these pregnancies. However, many US women -- including Alaska Governor Sarah Palin, whose son with Down syndrome, Trig, was a constant presence on last year's campaign trail -- are finding out their fetuses have the syndrome and are continuing with the pregnancy.

At their best, obstetricians provide their patients with information and counseling that empower them to make the right decision -- about testing, and about what to do with the results of these tests. As an obstetrician specializing in complex pregnancies, including those affected by Down syndrome, I try to be informative, supportive, and non-directive, but I recognize that the options are confusing and the decisions momentous.

Sonia and Dave, who both have engineering degrees from the Massachusetts Institute of Technology and who talked to me only if I did not use their real names, found the testing options and their interpretation to be unintelligible and the inability of these tests to provide a definitive answer maddening. The tests use mathematical formulas to estimate the chance a fetus will have Down syndrome and a handful of other conditions. The result is like a lottery no one wants to win: A 1-in-10,000 risk reassures the parents and their doctor that the chance of having a fetus affected with Down syndrome is extremely low (but never zero). In Sonia and Dave's case, the risk was 1 in 6. Ultrasound findings may modify these risk levels -- the echogenic bowel that Sonia's fetus had typically increases the risk of Down syndrome tenfold. Clinicians try to explain these results, but often clinicians themselves don't entirely get it. And emotions invariably complicate the interpretation of the data. As Dave puts it: "If the odds are 1 in 100 when you are playing cards, it's easy to decide what to do. However, when it's your child and your future, it's an entirely different matter."

To understand the screening test, consider 100 pregnant women, all of whom carry a fetus affected with Down syndrome. The best tests available would tell 95 of the women that they are at high risk for carrying a baby with Down syndrome and incorrectly tell five women that they are low risk. Now consider 100 women carrying babies without the syndrome. The same test would tell 95 women that they are at low risk of carrying a Down-affected fetus and tell five women incorrectly that they are at high risk.

Screening tests for Down syndrome that gained widespread acceptance in the 1980s and 1990s typically identify 70 percent to 80 percent of fetuses affected with the syndrome four months into a pregnancy. Now, the combination of blood work and an ultrasound done three months into a pregnancy can identify 85 percent of fetuses with Down syndrome, and the addition of results from a blood test done one month later increases the detection rate to 95 percent. Because none of these tests offer a definitive answer, they are often used to help women decide whether to have an invasive test -- amniocentesis or chorionic villus sampling -- and accept the small associated risk of miscarriage.

In their Westford home, surrounded by toys, dolls, and games favored by their firstborn, a 3-year-old girl, Dave recalls his initial response to hearing that their second child might be different: He favored abortion. However, his wife did not. "As a woman, you ask yourself, 'Can I love this baby as much as I would love any baby?' " Sonia says. "And I thought, 'I can love this baby no matter what.' . . . That made it tremendously difficult for me to make a decision, because how could I terminate a baby I love?"

They decided to undergo amniocentesis, so days later Peterson inserted a 3½-inch needle through Sonia's abdominal wall and into her uterus and watched carefully on ultrasound to make sure the active fetus stayed away from the needle while she drew off 4 teaspoons of amniotic fluid to do the test that could provide a definitive answer.

Three days later, Sonia took the call that confirmed their fears: Their child would have Down syndrome. "We went upstairs and fell apart," remembers Dave, sitting in their spacious living room, where the occasional box gives away the newness of the home. After he had seen their baby moving before their eyes on the ultrasound, Dave no longer wanted to terminate the pregnancy, now four months along, while Sonia was feeling overwhelmed. "I don't think I can do this," she remembers saying.

Given the improved accuracy of screening tests, it is probably not surprising that the number of babies born with Down syndrome in much of Europe and the developed world has declined. In one region of France, the number of babies born with the syndrome dropped from approximately 77 per year between 1981 and 1985 to 48 in 2005, in spite of a 50 percent increase in the annual number of births. In the United States, however, the number of babies born with Down syndrome has increased, from 1,676 in 1996 to 2,085 in 2006, the last year for which data are available from the Centers for Disease Control and Prevention. (Some experts, including those at the CDC, estimate the actual number of babies born in recent years with Down syndrome in the United States to be as high as 5,400 per year, although they do not dispute the upward trend over the past 10 years.)

Throughout the developed world, more women are conceiving fetuses affected by Down syndrome because they are having children later in life, and a woman's increasing age is the most important risk factor for the syndrome. Because of the enhanced availability of screening tests, these women can learn earlier in their pregnancy that their child will have Down syndrome. In much of Europe, women are using this information to choose abortion -- the abortion rate for Down syndrome in Paris, for example, is estimated to be 85 percent, one of the highest in the world. "We conclude that there are cultural differences, in terms of what women see as the norm, what cultural attitudes pervade, and what sort of counseling they are getting from their doctors," says Helen Dolk, a professor of epidemiology at the University of Ulster in Northern Ireland. In the United States, on the other hand, the decision to abort Down syndrome-affected fetuses appears to be made less frequently. While there are no reliable nationwide statistics, some information exists about specific areas: The abortion rate for fetuses affected with Down syndrome in Atlanta is 21 percent, for example, whereas it is 6 percent in Utah.

Two years ago, the American College of Obstetricians and Gynecologists recommended that all women be offered screening for Down syndrome, as well as amniocentesis or chorionic villus sampling, prompting concern among advocates for children with Down syndrome that the diagnosis would disappear among newborns -- but this fear appears unfounded. "Women put their own logic into it," says Dr. Mary D'Alton, the chairwoman of obstetrics and gynecology at Columbia University and leader of the renowned FASTER study, which compared different strategies to screen for Down syndrome. "It is not our logic that matters -- it's the logic that the patient brings to it that matters," D'Alton says.

There are many views on why improved screening for Down syndrome hasn't had the same effect on the number of US babies born with this condition as it has had in Europe. "I think that the US has a very diverse population, and I think that there are likely to be a tremendous diversity of opinions and perspectives about what to do with the information," says Dr. Adolfo Correa, leader of the birth defects surveillance team at the CDC's National Center on Birth Defects and Developmental Disability. Not only are pregnancy decisions influenced by women's culture, ethnicity, and religion but also by the availability of increasingly strong support services for children and adults with disabilities.

One evening early in her pregnancy, Gail Trinque remembers turning to her husband, Scott, and blurting out, "You know, there's a test for Down syndrome, and I don't want to have it, because it's not a great test, and I don't want to have an amniocentesis. And in any event, if we have a child with Down syndrome, we're going to have it anyway, right?"

Scott looked up from what he was doing, caught off guard by the logical sequence that she clearly had been wrestling with. "Right," Scott said, nodding in agreement.

"It was a short discussion," he remembers.

The Lakeville couple were looking forward to the ultrasound, done at 17 weeks in their doctor's office, when they would find out if their first child would be a boy or a girl. "You're having a boy," the ultrasound technologist told them, but she was distracted and kept looking at the fetus, moving the ultrasound wand around and around. Then she asked, "Did you have an AFP?" referring to the blood test that Gail had chosen to eschew.

"I knew something was wrong," Gail remembers. Scott adds, "It took a happy moment of 'Wow, we're having a boy,' and made it scary." Gail started to cry.

They went for a special ultrasound at South Shore Hospital, where the obstetrician diagnosed a heart defect and identified two other ultrasound markers for Down syndrome. "Let's do an amniocentesis right now," the doctor said, recommending the only test that could distinguish Down syndrome from another abnormality with certainty.

"The way he said it made sense to me," said Gail. And a week later, right before Christmas, they got a call confirming the Down syndrome diagnosis.

They visited a cardiologist, who drew a diagram of the atrioventricular canal defect that their fetus had, using red and blue markers to illustrate the flow of oxygenated and deoxygenated blood, and described the surgery that would be required early in their son's life. They visited a genetics specialist, who angered them with her negativity. "The first thing that you need to know is that this baby will not be like you," they remember her saying.

They got online, where most of the information they found was frightening. When Scott discovered that Down syndrome is associated with the congenital defect imperforate anus, where the rectum ends in a blind internal pouch without penetrating the skin, he shut down his computer.

One of their doctors offered abortion as an option to consider. "We did have that conversation," recalls Scott, the 36-year-old owner of a data-storage company. "We discussed how we could still decide to have this child or not."

"We're not religious," says Scott. "And we didn't decide to have Theo because of God. We just knew we could handle this."

Pretty soon they were focusing on preparing for Theo and for the cardiac surgery that would come soon after his birth. They built an addition on their house, where Gail's mother now lives, but someday the space will be for Theo.

One morning last summer, Theo, now 3, ran around the Trinque's comfortable living room, laughing and enjoying everyone in sight. His heart defect was repaired when he was 5 months old and has not caused problems since then. He goes to school, where he receives a host of special services.

When Theo was 18 months old, Gail became pregnant with his sister, Zoe, and again decided not to have the special screening for Down syndrome. "I just felt that there was no way I'm going to have another Down syndrome baby. It's impossible," Gail, who works part time as a physician assistant, says now. She didn't.

"I did the math," says the 35-year-old mother, "and part of the reason we had another child was so Zoe can help take care of Theo when we are old."

Dave and Sonia made similar rounds as Gail and Scott. They read about Down syndrome and met with Dr. Laurie Demmer, chief of genetics at the Floating Hospital for Children at Tufts Medical Center, who talked to them about what life would be like for their child and for their family. They learned about medical issues that can complicate the newborn period, as well as about mental retardation and what can and cannot be predicted. "I tell parents that the child will learn to read and write and walk and talk and will learn to do lots of things," says Demmer. "They'll just do it more slowly than their peers. . . . I emphasize that [the decision to terminate a pregnancy or not] is a very important decision -- it may be one of the most important decisions they will ever make in their lives. And they have to decide what's best for them."

"We're older parents," says Sonia. "Who would take care of this child when we could no longer do it? We would essentially be leaving this child for [our daughter] to take care of."

"I never see people who feel they made the wrong decision," says Demmer. "Whatever decision they reach always is the right decision. They make it the right decision."

Days after meeting with Demmer, Sonia and Dave came to Tufts Medical Center, where, in an operating room, the fetus was removed from her uterus.

"When you get pregnant, you start to plan for a life with two children," reflects Sonia. "You leave toys around that you might have put away and keep [children's] clothes accessible. So when this happens, you experience not only the loss of the child within you but the loss of this life that you had started, carefully, to build."

Dr. Adam J. Wolfberg practices maternal-fetal medicine at Tufts Medical Center in Boston. E-mail him at awolfberg@tuftsmedicalcenter.org.

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