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

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.

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.

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).

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.