The role of the placenta in the developmental origins of health and disease—Implications for practice

The placenta is actively involved in transporting nutrients to the fetus, it has both direct and indirect effects on fetal cardiovascular function and has endocrine influences on the mother and fetus. As such, a properly functioning placenta is crucial for normal fetal development and plays a central role in mediating effects of the maternal environment on the fetus. An altered external environment or abnormal placental function can induce developmental changes in the fetus and may have important consequences for the risk of cardiovascular and metabolic disease in adult life.The developmental origins hypothesis proposes that the early environment, from the periconceptional period until early childhood, can predispose an individual to adult cardiovascular and metabolic disease. This hypothesis is supported by epidemiological studies and by work in animals. These effects do not just act in low birth weight babies but have been shown to occur within the normal range of birth weight. It is thought that fetal adaptations to an impaired intra-uterine environment may enhance survival in early life but have deleterious effects in later life.Experimental studies suggest that maternal diet and body composition can alter placental structure and function, and we have recently demonstrated associations between a woman's nutritional state before pregnancy and placental function at term. To elucidate these relationships, further work is needed to define markers of placental function and to characterize their relation to rates of fetal growth.Understanding how the placenta mediates maternal influences will be crucial in determining the mechanisms underlying developmental programming. This will allow the design of targeted public health interventions, both before and during pregnancy, to enhance placental function and thereby improve the health of the offspring throughout life.