Is your baby at risk for Down's syndrome? Find out as early as 11 weeks
There's a new test that tells expectant parents whether their baby is at risk for Down's syndrome as early as 11 weeks.
This new test is called first trimester screening, and it is extremely accurate in detecting the common chromosomal variation that causes Down's syndrome. The test also helps identify the chromosomal disorder, trisomy 18 and some congenital heart abnormalities.
"First trimester screening is one of the earliest fetal risk assessments we can perform," states Shailen Shah, MD
, Virtua maternal-fetal medicine specialist.
To participate in first trimester screening, women who are 11 to 14 weeks pregnant undergo an ultrasound and a blood test. The blood test detects human chorionic gonadotropin (HCG) and pregnancy-associated plasma protein (PAPPA). If these protein levels are off, the risk of having a child with Down's syndrome is higher.
Specially certified sonographers perform a fetal ultrasound to determine the skin thickness of the baby's neck, which also helps detect Down's. Blood test and ultrasound results are then reviewed by maternal-fetal specialists and presented to the patient within a week.
"Examining both of these tests together significantly increases the accuracy in determining the risk for this disease," notes Dr. Shah. "In fact, we can detect nearly 85% of all cases based on the results of this screening."
Dr. Shah also notes the advantages of this screening: "Mothers who show a low risk for a baby with Down's syndrome are put at ease early in their pregnancy, and those who show a high risk are able to look into follow-up testing, do research and seek support before their child is even born." According to Dr. Shah, it's helpful to connect these parents with other couples who already have children with Down's syndrome so they can prepare for the special needs their child may have.
It's important to note that no screening provides 100% accuracy. "Sometimes it's difficult for people to remember that this is a screening, not a diagnosis," says Dr. Shah. "So even if results indicate a significant risk, it's still possible that the baby could be born without birth defects."
For more information about first trimester screening or maternal fetal medicine, call 1-888-Virtua-3
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Shailen Shah, MD, is a graduate of Jefferson Medical College in Philadelphia. He completed a residency in obstetrics and gynecology as well as a fellowship in maternal-fetal medicine at Thomas Jefferson University Hospital. Dr. Shah is certified in maternal-fetal medicine and is specially trained to provide critical care to pregnant women. He has also lectured nationally on the topic of high-risk pregnancies.