Maternal Immune Activation

Normal pregnancy requires epigenetic reprogramming that downregulates Th1 responses and promotes Th2 and T-regulatory cells to prevent immune attack on the genetically foreign fetus. Gestational diabetes reverses the protective pregnancy immune shift and produces a pro-inflammatory maternal bloodstream that passes cytokines across the placenta to the developing fetal brain. Chronic stress produces tonic NF-κB activation through cortisol receptor resistance, and adverse childhood events can reprogram the hypothalamic-pituitary-adrenal axis into this dysregulated state persisting into pregnancy. Maternal autoantibodies against fetal brain proteins including CRMP1 and CRMP2 form in response to toxin exposure, nutritional shifts, or infection and destroy fetal neurological development throughout pregnancy. Maternal SARS-CoV-2 infection during pregnancy is associated with an odds ratio of 1.94 for ASD at one year. Maternal obesity alone doubles baseline ASD risk in offspring. Colostrum from mothers with gestational diabetes contains elevated pro-inflammatory cytokines (IFN-γ, IL-6, IL-15) and reduced anti-inflammatory IL-1RA, transmitting dysregulated immune signals to infants after bi…