Nuchal translucency poised for wider use in U.S. (Still Not Standard of Care).

ASHEVILLE, N.C. - The addition of a nuchal translucency measurement to the standard multiple serum markers for aneuploidy can increase the detection rate of Down syndrome from 75% to 90%, but it will be some time before this is standard practice in the United States, Dr. Marshall St. Amant predicted.

"It is already practically a done deal in the United Kingdom and Europe, but the American College of Obstetricians and Gynecologists' last position paper on it in 1999 said it was still investigational and is not recommended for routine clinical use," said Dr. St. Amant, a maternal-fetal medicine specialist at Louisiana State University, New Orleans.

Still, the publication of a study last year in the Lancet rekindled interest in increasing the detection rate achieved with multiple marker screening by adding other tests, he said during the annual Southern Obstetric and Gynecologic Seminar.

The study found that the combination of free [beta]-hCG, estradiol, pregnancy-associated plasma protein, alpha-fetoprotein, and nuchal translucency measurements, along with the absence of a fetal nasal bone at 1011 weeks' gestation, achieved a Down syndrome detection rate of almost 98% (Lancet 358[9294]:1665-67, 2001).

An editorial in the same issue maintained that it's time for a total shift to first-trimester screening for Down syndrome.

"Their final detection rate of 98% was very alluring, plus the fact that this test enabled very early detection, but it's very difficult to determine the presence of the nasal bone in a fetus of this age," he said.

"I think what ACOG will probably eventually consider is a more classic position on the combination of ...