Intrauterine nutrition and development

Abstract

The maternal-fetal exchange of nutrients involves several maternal and placental metabolic and hormonal pathways each of which is influenced by factors such as maternal nutritional status before and during pregnancy maternal anthropometric characteristics life-style maternal hormonal milieu adaptation to gestation-induced physiologic changes local factors influencing placental growth and fetal development. Maternal nutritional factors are the most important determinants of intrauterine growth retardation. There is evidence that maternal peri-conceptional status also affects embryogenesis including the development of neural tube defects. Fetal growth entails both active cell replication (hyperplasia) and increments in cell size (hypertrophy). The brain is the organ at greatest risk during intrauterine life since it is the first organ to complete hyperplastic growth. Placental metabolic functions are critical in early pregnancy to providing nutrition and energy to the developing conceptus and the placenta itself while placental endocrine activities are important to maintaining pregnancy and inducing metabolic adaptations in the mother and fetus. Premature infants face both possible nutritional deficits and lack of placental nourishment placing them at increased risk of neuro-developmental disorders especially if they are also low birth weight. Emerging knowledge on the capacity of the fetus to elaborate hormonal signals toward both the placenta and the mother to regulate the flow of nutrients and activate the placental growth factors should become the basis of new research programs in the field of intrauterine development.