Our study shows that prenatal LNG exposure induces ERβ suppression in the amygdala in offspring with autism-like behavior, which includes significantly less buried marbles and interaction time in the social behavior test and spending much less time in the open arm and more time in the closed arm in the EPM test, as well as spending less time in the central area and more time in the peripheral area in the open-field test. This evidence concerns the gene ESR2 and autism.