Placental changes in idiopathic intrauterine growth restriction

Abstract Introduction Placenta is the maternal–foetal contact zone. The placentas of ‘idiopathic’ intrauterine growth retardation babies may hold the key to the aetiology of growth restriction. It was noted by most workers that in cases of intrauterine growth retardation placentas, there were some abnormal positions of insertion of umbilical cords, placental weight and volume was significantly lower than the controls and they also had smaller diameters. The greater placental coefficient in intrauterine growth retardation indicates that though both placentas and babies in intrauterine growth retardation had less weight, placental sizes were not relatively less. This article aims to review literature to identify any morphological and structural peculiarities of placenta that might contribute to development of idiopathic intrauterine growth retardation. Discussion Light microscopy suggested that syncytiotrophoblastic lining was more degenerated and a number of syncytial knots increased in intrauterine growth retardation placentas than that of the control placentas. X cells were present in both the cases, though more in intrauterine growth retardation. Intravillous and perivillous fibrin depositions were markedly increased in intrauterine growth retardation; also there were more hypovascular/avascular villi and large areas of infarction. Conclusion Review of the literature to establish any relationship between placental histomorphometric changes and intrauterine growth retardation suggests that intrauterine growth retardation pregnancies are associated with reductions in villous tree elaboration, particularly affecting the volume and surface area of terminal and intermediate villi, thereby restricting surface area over which foetomaternal exchange may occur. Thus, placental oxygen transfer might be reduced, thereby restricting foetal growth and development.