The exact cause is unclear. However, several risk factors have been identified. Consistently described risk factors include formula feeding, intestinal dysbiosis, low birth weight and prematurity. Maternal factors like chorioamnionitis, cocaine abuse, in-utero growth restriction, intrahepatic cholestasis during pregnancy, increased body mass index, lack of prenatal steroids, mode of delivery, placental abruption, preeclampsia, and smoking have not been consistently implicated with the development of necrotizing enterocolitis. Other risk factors potentially implicated include congenital heart disease, birth asphyxia, exchange transfusion, and prelabor rupture of membranes. The underlying mechanism is believed to involve a combination of poor blood flow and infection of the intestines. Diagnosis is based on symptoms and confirmed with medical imaging.