TUESDAY, Jan. 2, 2007 (HealthDay News) -- All pregnant women should be offered screening for Down syndrome, regardless of their age, according to new guidelines from the American College of Obstetricians and Gynecologists (ACOG).
Down syndrome is a common disorder that is caused by an extra chromosome. It can result in congenital heart defects and mental retardation.
Previously, genetic counseling and testing for Down syndrome by amniocentesis or chorionic villus sampling (CVS) was automatically offered to women aged 35 and older. Now, the ACOG recommends that pregnant women of all ages consider less invasive screening options for assessing their risk of Down syndrome before the 20th week of pregnancy.
"This new recommendation says that the maternal age of 35 should no longer be used by itself as a cut-off to determine who is offered screening vs. who is offered invasive diagnostic testing," Deborah Driscoll, vice chairwoman of ACOG's Committee on Practice Bulletins-Obstetrics and co-author of the new guidelines, said in a prepared statement.
The decision whether to have amniocentesis or CVS is a complex one. There is a small risk of pregnancy loss from an invasive procedure, but factors that increase a woman's risk of carrying a baby with Down syndrome may outweigh the small risks of the procedure in some cases.
The goal of these new guidelines, which were published in the January issue of Obstetrics & Gynecology, is to offer screening tests that have high rates of detecting Down syndrome.
The guidelines provide physicians with suggested screening strategies and discuss the advantages and disadvantages of each test. A number of factors should be considered when deciding which screening test is optimal, including how far along the pregnancy is, whether the woman is carrying multiple fetuses, personal and family history, and which tests are available.
The ACOG recommends using nuchal translucency (NT), an ultrasound exam that measures the thickness at the back of the neck of the fetus, along with a blood test that screens for Down syndrome during the first trimester.
Women who are found to be at increased risk by this first trimester screening should be offered genetic counseling and the option of CVS or amniocentesis.
The ACOG also recommends neural tube defect screening in the mid-trimester to women who elect only first-trimester screening for Down syndrome.
More information
The Nemours Foundation has more about prenatal tests.
