Evaluation of sporadic bovine alkaline phosphatase interference in the Beckman Access unconjugated estriol (uE3) assay affecting maternal serum screening results.

Objectives: Bovine alkaline phosphatase (BALP) mediated interference is a potential issue in the Beckman Access unconjugated estriol (uE3) assay. As the uE3 assay is a component of second trimester maternal serum screening characterizing this interference is essential for delivering accurate trisomy 18 and trisomy 21 risks.

Design And Methods: Residual serum samples (n = 517) were measured by two different lots of uE3 assay.