Maternal immune activation during pregnancy is associated with more difficulties in socio-adaptive behaviors in autism spectrum disorders.

Background: Autism spectrum disorders (ASD) are neurodevelopmental disorders characterised by deficits in social communication or interaction and repetitive behaviours. Maternal immune activation (MIA) during the mid-pregnancy is a known risk factor for ASD. Although reported in 15% of affected individuals, little is known about the specificity of their clinical profiles. Adaptive skills represent a holistic approach to a person's competencies and reflect specifically in autism, their strengths and difficulties. Methods In this study, we hypothesised that individual with ASD with a history of MIA (MIA + ) could be more severely socio-adaptively impaired than those without MIA during pregnancy (MIA − ). To answer this question, we considered two independent cohorts of individuals with ASD (PARIS study and FACE ASD) screened for pregnancy history, and used a supervised and unsupervised statistical approach. Results We included 295 mother-child dyads with 14% of them with MIA + . We found that ASD-MIA + individuals displayed more severe maladaptive behaviors, specifically in their socialization abilities. MIA + directly influenced individual's socio-adaptive skills, independent of other covariates, including ASD severity. Interestingly, MIA + may affected persistently the socio-adaptive behavioral trajectories of individuals with ASD. Limitations The current study has a retrospective design with possible recall bias regarding the MIA event and, even if pooled from two cohorts, has a relatively small population. In addition, we were limited by the number of covariables available potentially impacted socio-adaptive behaviors. Larger prospective study with additional dimensions related to ASD is needed to confirm our results Conclusions Specific pathophysiological pathways may explain these clinical peculiarities of ASD- MIA + individuals, and may open the way to new perspectives in deciphering the phenotypic complexity of autism and for the development of specific immunomodulatory strategies.