Intrauterine nutrition: its importance during critical periods for cardiovascular and endocrine development.

Experimental investigations in animals have highlighted the role of early reduced calorie and protein nutrition on fetal cardiovascular development, and the occurrence of a transition from a low fetal arterial blood pressure in late gestation to a high arterial blood pressure postnatally. These observations may explain the correlation between health, including appropriate nutrition, in pregnant women and the outcome of their pregnancies. Emphasis has been placed on low birth weight infants who have an increased risk of developing cardiovascular diseases, including hypertension, coronary heart disease and stroke in adulthood. Vascular pathology in adults is not always associated with low birth weight and animal experiments indicate that substantial changes in cardiovascular and endocrine function can result from maternal or fetal undernutrition without impairing fetal growth. Experimental investigation on organogenesis shows the pivotal role of adequate protein availability as well as total caloric intake. Amino acid metabolism in the feto-maternal unit appears to have a key influence on the development of organs involved in chronic degenerative disease in the adult. Experimental investigation has also highlighted the role of carbohydrate metabolism and its effect on the fetus in this respect. Either restriction of protein intake or diabetes in pregnant rats has intergenerational effects at least on the endocrine pancreas and the brain. Further investigation is needed to clarify the mechanisms involved and lead to a new understanding of the importance of nutrition during pregnancy. This will provide an important approach to the primary prevention of diabetes and chronic degenerative diseases.