OK to test for Down syndrome? It's complex

Prenatal diagnosis is now much easier and safer. But it is a mix of conflicting -- and sometimes hidden -- agendas.

Steve Calvin

Minneapolis-St.Paul Star Tribune

Published January 7, 2007

The maternal instinct that motivates pregnant women is powerful and truly remarkable. In more than 25 years of obstetrical practice, I have seen mothers subject themselves to painful procedures, nasty medications and months of tedious bed rest -- all motivated by the desire to nurture and protect a healthy baby. Fortunately most of their efforts are rewarded.

Early pregnancy can be a mixture of anticipation and anxiety. The possibility of abnormality always lurks in the back of a mother's mind. One of these abnormalities is Down syndrome -- caused by the presence of an extra chromosome 21. It occurs at conception, and the risk increases with maternal age. In an unscreened population, 1 in 800 babies are born with DS. In Minnesota, that would be 75 to 80 children per year, or 5,000 in the entire United States. Approximately 350,000 people with DS are currently our fellow citizens.

Down syndrome causes significant health problems and social challenges. No parent would deliberately make their daughter or son face a life with DS, but many parents accepted the challenge when it came. In this they have many advocates and much support through organizations such as the Down Syndrome Association of Minnesota. There is even a waiting list of families willing to adopt DS children.

But I believe that we are at a tipping point. The counterweight to societal support for people and families with DS is the expanding availability and promotion of prenatal DS screening tests. When DS is confirmed, abortion is offered. Increasingly, it is chosen. In England and some major U.S. cities, more than 90 percent of DS fetuses are aborted.

Now the American College of Obstetricians and Gynecologists recommends offering Down syndrome screening to all pregnant women. A Dec. 31 AP story in the Star Tribune explained why invasive tests such as amniocentesis were previously offered only to pregnant women older than 35, and why advances in noninvasive testing now make it "safer" to offer the test to all 4 million women who receive pregnancy care each year.

The new, noninvasive prenatal screening involves both ultrasound and lab testing done in the first 3 months. Almost all fetuses with DS can be detected with fewer women requiring amniocentesis, a painful diagnostic procedure that has a small but real risk of miscarriage.

I am all for decreasing unnecessary medical tests and for increasing the accuracy of the testing that we do. But I also support responsible use of medical resources, prudent public policy, truly informed consent, and ethical consistency. The newly promoted testing for DS deserves critical examination on all these accounts.

As physicians, we have many motivations to offer screening tests, not the least of which is fear of a potential lawsuit for a failed diagnosis. To be fair, most of my colleagues are simply motivated by a desire to maximize choices for patients. Abortion is not always chosen. Prenatal diagnosis is a major advance in obstetrics when it allows appropriate care at birth. But is facilitating the prenatal destruction of "less-than-perfect" life a medical advance?

Some published cost-benefit analyses ominously promote DS screening using the "cost" to society of a DS life and the cost of tests and abortion. At best, this is an affront to parents who were told their DS child would never be able to count change, but now functions as a productive taxpaying member of society. And the $1,000 or more that testing will really cost for each pregnant women is going to be a health care bank-breaker.

Is decisionmaking truly informed when screening is offered using questions such as, "You want to do everything for your baby, don't you?" Prenatal diagnosis is a mix of conflicting, unacknowledged and sometimes hidden agendas. Many women tell me of the subtle and overt pressure that they have felt to undergo prenatal screening and to have an abortion if DS is found.

The promotion of DS screening is analogous to supporting equal educational opportunity for children as long as they make it to school, while allowing and even encouraging overt discrimination toward some kids at the bus stop. This kind of ethical incoherence is unsustainable in a truly caring society.

Steven Calvin is a Minneapolis physician and cochair of the Program in Human Rights and Health at the University of Minnesota.