Maternal serum alpha-fetoprotein screening: a report of the Forsyth County project.

A pilot screening program for the prenatal detection of neural tube defects has been conducted in Forsyth County, North Carolina. During the first 2 years of the program, 3,476 women were screened by quantitating levels of maternal serum alpha fetoprotein. Three neural tube defects and one case of multiple congenital anomalies with severe gastroschisis were detected as a result of the screening program. Outcome of pregnancy has been monitored in this group of women and no false negatives have been reported. No false positive amniotic fluid alpha-fetoprotein values were observed and no normal fetuses were aborted. Data gathered from this screening program again document the validity of maternal serum screening. The method of implementing a program for the prenatal decision of neural tube defects in urban areas is discussed.