New screening helps to determine risk for having a baby with Down syndrome

Obstetricians at Thomas Jefferson University Hospital, Philadelphia, are offering a new, quicker, option for pregnant women who choose to undergo first trimester screening. The screening helps to determine whether the woman is at increased risk for having a baby with Down syndrome.

The test has two components--a blood test and an ultrasound examination. Previously, Jefferson patients who underwent the first trimester screening received results within a week. Now, these same women receive results within an hour of the ultrasound.

“This option is a real advance for parents who are concerned about having a baby with Down syndrome,” said Stuart Weiner, M.D., who is director of the Division of Reproductive Ultrasound and the Genetics Program in the Department of Obstetrics and Gynecology at Thomas Jefferson University Hospital. “The quick turnaround, which is available only in the Philadelphia area at Jefferson, provides much greater peace of mind —at the same cost as the traditional screening,” he said. “In fact, this is the only such program in the United States.”

Thomas Jefferson University Hospital was the lead site for the original national study in 1999 to determine whether blood tests and a specific ultrasound measurement would offer expectant parents a more accurate assessment of the risk of Down syndrome during the first trimester of pregnancy.

“This test identifies whether there is a potential problem in up to 90 percent of pregnancies,” said Dr. Weiner, who is also associate professor of Obstetrics and Gynecology at Jefferson Medical College of Thomas Jefferson University.

The blood test, which can be done as part of a woman’s first prenatal tests, measures human chorionic gonadotropin beta-hCG and plasma protein A (PAPP-A)—both markers for Down syndrome. The ultrasound, which is performed at any time between 10 and 14 weeks, measures nuchal translucency—the thickness of the skin at the back of the neck of a developing fetus. An abnormally large neck fold may indicate a greater risk of Down syndrome.

At Thomas Jefferson University Hospital, the patient has the test results within an hour of the ultrasound.

Patients who test positive will be recommended for genetic counseling and the option of chorionic villus sampling (CVS) on the same day. CVS is the diagnostic test for Down syndrome in the first trimester.

For information about prenatal testing or to make an appointment with a Jefferson obstetrician or gynecologist, call 1-800-JEFF-NOW or 215-955-2112.