In this study, we shed light on the possibility that NEC arises from reduced AHR signaling in the intestinal epithelium of the premature infant, and show that AHR ligands may be passed from mother to infant—both during pregnancy via the fetal circulation, and in the postnatal period through the breast milk—where they can then attenuate the severity of this disease. Here, AHR is linked to necrotizing enterocolitis.