RISK OF ANOMALIES AS A FUNCTION OF LEVEL OF ELEVATED MATERNAL SERUM ALPHA-FETOPROTEIN

OBJECTIVE: Most neural tube defects risks are not actual but mathemati c extrapolations. We sought to evaluate this risk and to compare actua l performance. STUDY DESIGN: This was a retrospective study of a refer ral population with elevated maternal serum alpha-fetoprotein results between 1987 and 1992. Ultrasonography results, delivery records, and autopsy results were compared with entry levels of maternal serum alph a-fetoprotein, and the percentage of fetal anomalies detected in this study was evaluated. RESULTS: A total of 773 patients with elevated ma ternal serum alpha-fetoprotein levels were evaluated. There was a prog ressive increase in the incidence of anomalies as a direct function of the level of the maternal serum AFP, varying from 3.4% at a level of 2.5 to 40.3% at a level >7.0. CONCLUSION: Data from this study support the correlation of maternal serum AFP levels with the risk of neural tube defect and ventral wall defects.