Gross pathology of the placenta in intrauterine growth retardation.

A prospective study of placental pathology in intrauterine growth retardation (IUGR) has been performed with a total of 223 placentas during a ten-year period. The material is divided into subgroups with or without hypertensive complications of pregnancy. Velamentous insertion, single umbilical artery (SUA) and placental infarct occurred more frequently in the IUGR group than in a reference material comprising 500 normal deliveries. Such a prevalence was not observed with marginal insertion, circumvallate placenta or true knot formation. Velamentous insertion and SUA, probably compromising the foetal blood circulation to some extent, occurred more frequently in the normotensive group than in the hypertensive group. Seven out of 11 cases with SUA were associated with foetal malformations. Anomalies in the placenta and in the umbilical cord affecting the foetal blood circulation are simple to recognize by naked-eye examination. Our prospective study of placentas in a series of IUGR cases shows that a routinely performed examination of the placenta in the delivery department may help to clarify the pathogenesis of retarded foetal growth in normotensive pregnancy.