Medical Research: What is the background for this study? What are the main findings?
Dr. Walker: Autism spectrum disorder (ASD) is a neurobehavioral condition identified in 1 in 68 U.S. children and is part of a broader group of developmental disabilities that affects 1 in 6 children. Growing evidence suggests that Autism spectrum disorder and developmental delay originate during fetal life. Preeclampsia is a complicated and frequently dangerous pregnancy condition that appears to arise from a shallow placental connection and may increase the risk of abnormal neurodevelopment through several pathways.
Medical Research: What are the main findings?
Dr. Walker: Children with Autism spectrum disorder were more than twice as likely to have been exposed to preeclampsia compared with children with typical development. Risk for ASD was increased further in children born to mothers with more severe presentations of preeclampsia. Mothers of children with developmental delay were more than 5 times more likely to have had severe forms preeclampsia – often with evidence of reduced placental function – compared with mothers of children with typical development.
Medical Research: What should patients take away from your report?
Dr. Walker: Preeclampsia is more common in women who are obese or who have diabetes or high blood pressure before pregnancy. While not proven, it makes sense that normalization of maternal weight by healthy eating and exercise prior to pregnancy is likely to improve pregnancy outcomes overall and may reduce the risk of preeclampsia. Further, continuing healthy diet and exercise behaviors through pregnancy keeps weight gain within recommended guidelines and is likely also to keep pregnancy as healthy as possible.
Medical Research: What should clinicians take away from your report?
Dr. Walker: The cumulative evidence supports efforts to reduce preeclampsia and its diminish severity in order to improve neonatal outcomes including neurodevelopment. The public health implications of these findings are considerable given that over half of pregnant women are overweight or obese, which is a risk for preeclampsia. These findings add to a growing body of evidence that supports programs to help women optimize metabolic health before conception and throughout pregnancy. Administration of low-dose aspirin has shown modest benefit in reducing the incidence of preeclampsia. Once preeclampsia has been diagnosed, the risk-benefit analysis regarding when to deliver may continue to shift in favor of earlier intervention in the setting of worsening preeclampsia severity, particularly in women manifesting signs of placental insufficiency. Subtle restriction of nutrient and oxygen supplies may have lasting impacts on the developing fetal brain that warrant intervention before profound signs and symptoms appear.
Support: Findings were generated by the CHARGE (CHildhood Autism Risk from Genetics and the Environment) case-control study through the University of California, Davis and funded by the National Institute of Environmental Health