Objective: Maternal serum alpha-fetoprotein (MSAFP) values are reported to be lower in type 1 diabetic patients, and a correction factor is often applied. We sought to determine whether type 2 diabetic patients require the same MSAFP adjustments as type 1 diabetic patients.
Study design: We performed a retrospective review of MSAFP levels from a university laboratory in type 1 and type 2 diabetic patients between July 2000 and August 2006, matched 1:2 with controls. Groups were compared using analysis of variance and Student t testing.
Results: Seventy-seven type 1 and 75 type 2 diabetic patients were compared with 304 controls. Type 1 and type 2 diabetic patients differed significantly from each other and controls before corrections. Diabetic patients were similar to each other, but significantly lower than controls, after weight corrections. These differences were eliminated by a 10% correction factor.
Conclusion: Type 1 and type 2 diabetic patients require both weight and diabetes corrections to adjust MSAFP values to nondiabetic levels.