Maternal high-fat diet acts as a stressor increasing maternal glucocorticoids’ signaling to the fetus and disrupting maternal behavior and brain activation in C57BL/6J mice

•HFD mediates an imbalance in the expression of the genes that regulate the time window of fetal exposure to maternal glucocorticoids.•HFD disrupts behavior of the dam both before and after parturition.•HFD reduces neural activity in brain regions involved in olfactory processing and social recognition.•HFD feeding is a stressful challenge during pregnancy with relevant consequences on fetal development.