SEATTLE, Feb. 5, 2004 - Researchers from Swedish Medical Center's Division of Perinatal Medicine helped present findings from the National Institutes of Health-funded FASTER (First- and Second-Trimester Evaluation of Risk) Trial at today's 24th Annual Meeting of the Society for Maternal-Fetal Medicine (SMFM) in New Orleans. Results from the multi-center study indicate that a new prenatal screening test is effective at detecting Down syndrome earlier than ever, which allows couples to learn whether their child is at risk as early as the first trimester of pregnancy.
Currently, women are offered a blood test for Down syndrome around the 16th week of pregnancy. The FASTER Trial was designed to evaluate the effectiveness of a new screening done between the 10th and 14th weeks of pregnancy that involves a blood test and ultrasound to measure the thickness of a specific area on the neck of the fetus. This is important because a larger measurement of the neck area may indicate an increased risk for Down syndrome as well as other chromosomal and cardiac disorders. The study also looked at how effective a Combined test - involving the ultrasound and blood tests - was at identifying Down syndrome, which occurs in about one in every 800 live births.
The objective of the trial was to compare the performance of first- and second-trimester screening methods for the prenatal detection of Down syndrome. Unselected patients with singleton (single fetus) pregnancies at between 10 3/7 to 13 6/7 weeks were recruited. All patients had a first-trimester Combined test and returned at between 15 and 18 weeks for a second-trimester Quad blood test. Participants were then followed until they had given birth.
Results were based on 33,557 pregnancies (84 with Down syndrome) with complete first- and second-trimester data. With the Combined test, the detection rate was 76 percent with a 3.2 percent false-positive rate. With the Quad blood test, the detection rate was 84 percent with an 8.4 percent false-positive rate. From these statistics, researchers concluded that first-trimester Combined screening and second-trimester Quad screening are similarly effective. Fully integrated screening (using both approaches) had the highest detention rate with the lowest false-positive rate.
"The results of this trial essentially improve the extent to which people without Down syndrome are correctly classified as having the disease or not, which reduces unnecessary amniocentesis and more accurately identifies which women require more invasive screening," said David Luthy, M.D., director of Swedish Medical Center's Division of Perinatal Medicine. "I strongly suspect the results of this trial will change the way women get screened for Down syndrome."
Swedish was one of just 15 sites nationwide that took part in this trial, which began in October 1999 thanks to a multi-million grant from the NIH. Other centers included: Columbia University, New York; Wolfson Institute of Preventive Medicine, London, UK; Brown University, Providence, RI; University of Utah, Salt Lake City; William Beaumont Medical Center, Royal Oak, MI; University of Texas Medical Branch, Galveston; Mount Sinai Medical Center, New York; Albert Einstein College of Medicine, New York; University of Colorado Health Sciences Center, Denver; Tufts University, Boston; New York University; University of North Carolina Medical Center, Chapel Hill; and DM-STAT, Boston.
Due to the importance, size and scope of the FASTER Trial, 13 separate presentations related to different aspects of the study are being given at this week's SMFM conference. Results of the study will likely be published later this year in a major medical journal.
The Society for Maternal-Fetal Medicine was established in 1977 and is the membership organization for obstetricians/gynecologists who have additional formal education and training in Maternal-Fetal medicine. There are currently about two thousand active members of the Society. The Society hosts an annual scientific meeting in which new ideas and research in the area of Maternal-Fetal Medicine are discussed and there are additional frequent Continuing Medical Education courses provided by our members throughout the world. The Society is also an advocate for improving public policy and expanding research funding and opportunities in the area maternal-fetal medicine. For more information, visit www.smfm.org.