Insulin increases placental triglyceride as a potential mechanism for fetal adiposity in maternal obesity

•Maternal obesity is linked to excess adiposity in newborns.•Abundant insulin receptor is present in placentae from women of normal weight and obesity, and IGF-2 affects placental size and fetal growth.•Insulin and IGF-2 drive triglyceride accumulation in placental villous explants.•Insulin and IGF-2 stimulate esterification, but not de novo lipogenesis in the placenta.•Insulin regulates lipid metabolism and storage in the placenta.