Hypertension in pregnancy as a possible factor for child autistic behavior at two years old

•The association between hypertensive disorders of pregnancy and child autistic behavior at two years old was investigated on 6,794 children in Japan.•Superimposed preeclampsia was associated with child autistic behavior.•Early prediction in childhood is necessary to support child development. We investigated the association between hypertensive disorders of pregnancy (HDP) subtypes and child autistic behavior to accumulate the evidence. We found the association between superimposed preeclampsia and autistic behavior in children aged two years old by investigating 6794 mother-child pairs in the birth cohort study. Since early intervention for autism-spectrum disorder might be effective, it suggests that early prediction is necessary for children born of mothers who developed particularly superimposed preeclampsia to support their development. Not only for introducing early prediction, but also research for establishing effective intervention is necessary.