Autism spectrum disorders and maternal serum alpha-fetoprotein levels during pregnancy

Abstract

Objective: Numerous studies have been trying to disentangle the complex pathophysiology of autism spectrum disorders (ASD). In our study, we explored the potential role of maternal serum (MS) alpha-fetoprotein (AFP) in the prediction and the pathophysiology of ASD. Methods: A total of 112 patients with ASD and 243 control subjects were included in a case-control study, using a historic birth cohort maintained at Statens Serum Institute. Measurements of MS-AFP were obtained from a multicentre screening program, whereas clinical data were obtained from nationwide registers. Association between MS-AFP and ASD status was analyzed using logistic regression models and nonparametric tests. Results: Crude, but not adjusted, estimates showed that MS-AFP levels were slightly, but significantly, higher in mothers of children with ASD, compared with their control subject counterparts. People with ASD had an odds ratio of 2.33, with 95% confidence intervals of 1.00 to 5.39, to have MS-AFP above 2.5 multiple of median. Excluding subjects with congenital malformation comorbidities did not alter the direction of our estimates (OR 2.60; 95% CI 1.04 to 6.51, P = 0.04). Conclusion: Biologic plausibility of its role in the pathophysiology of ASD makes AFP a good candidate for further larger-scale studies to confirm such an association and to determine whether this pattern is unique to ASD or related to other psychiatric disorders as well.