Prenatal testing for Down Syndrome

Many pregnant women want to know if they are at risk of having a child with Down syndrome and choose to undergo tests that can provide useful information. This aspect of pregnancy can be extremely stressful and is often confusing. The following information will help expectant mothers better understand Down syndrome and the tests most commonly used to evaluate a woman’s risk of having a child with this condition.

What Is Down Syndrome?

Down syndrome is a genetic disorder caused by an extra chromosome – or part of a chromosome. Children born with Down syndrome have some degree of mental retardation, which ranges from mild to moderate, depending on the child. They also have facial features that may include eyes that slant upward, small ears that fold over at the top and noses with flattened bridges, as well as other physical traits such as short stature. Heart defects, increased infections, problems with vision and hearing and other health issues are also common in children with Down syndrome. That said, children with Down syndrome usually can do most things that any young child can do, such as walking, talking and dressing themselves.

Who Is at Risk for Having a Child With Down Syndrome?

The risk of Down syndrome increases as a woman ages. A 20-year-old woman has a 1 in 1,500 chance of having a child with Down syndrome whereas a 42-year-old woman has a 1 in 55 chance. But even though older women and parents who have already had a child with Down syndrome are at greatest risk, 80 percent of babies with Down syndrome are born to mothers younger than 35. Why? Because younger women have more babies than older women.

Screening Tests

When it comes to prenatal testing for Down syndrome, women have several options available to them, depending on where they receive their health care.
Screening tests do not provide definitive answers regarding a baby’s health. Rather, they indicate the likelihood of your child having Down syndrome. For example, a woman might be told she has a 1 in 600 chance of having a baby with Down syndrome. That means it’s unlikely that her child will have the condition, but there’s no guarantee that she’s not that one woman in 600 who is carrying a child with Down syndrome. Currently, there are two commonly used screening read more