Distal villous immaturity

Distal villous immaturity (DVI) is a placental phenotype characterized by enlarged distal villi with excessive stroma, hypercellular villous trophoblast, paucity of vasculosyncytial membranes, and a decreased fetoplacental weight ratio. It is predominantly observed in term or near-term placentas and is associated with specific maternal conditions including impaired glucose tolerance, obesity, and excessive pregnancy weight gain. A similar phenotype is observed in placentas with hypercoiling of the umbilical cord. DVI is also occasionally seen in the placentas of preterm infants with idiopathic fetal growth restriction, congenital malformations, and genetic or chromosomal abnormalities. In infants of diabetic mothers, DVI may in part be a consequence of excessive maternal glucose leading to release of fetal insulin and other growth factors that promote excessive placental growth at the expense of villous maturation. Adverse outcomes associated with DVI include intrauterine fetal death (IUFD), fetal growth restriction (FGR), and, more speculatively, late gestational hypoxia and chronic diseases of childhood and later adult life.