Historical reasons have led to knowledge that would not have been possible to obtain through research without gross violations of ethical norms. Quantification of macro- and micro-nutrient intake is hampered by a number of barriers. It has been observed that changes in fetal nutrition and its endocrine status can result in developmental adjustments that permanently alter the structure, physiology, and metabolism of children, thus exposing individuals to the risk of metabolic, endocrine, and cardiovascular diseases in adulthood. In research on the process better known as "fetal programming", the influence of the in utero environment on the epigenetic mechanisms of the fetus has been observed. Decreased or increased amounts of food intake may interfere with placental function and interfere with fetal growth. Altered placental function can lead to endothelial dysfunction, leading to changes in fetal growth and development. More recently, there has been increasing research on the impact of dietary supplementation on pregnant women and perinatal outcome. Among the more frequently examined variables are micronutrients such as folic acid, antioxidants, iron, magnesium and zinc, but also polyunsaturated fatty acids. The Covid-19 pandemic further highlighted the need to create disease registries and systematically monitor data, especially given the differences in health care availability on one hand and the incredible global differences in nutrient availability on the other
