During intensive development phases, such as pregnancy and childhood, the probability of insufficient nutrient supply raises. In the course of a vegan diet, the focus should be on an adequate supply of vitamin B12, zinc, iron, calcium, vitamin D, iodide, omega-3 fatty acids and iron. Nutrient deficiency can be prevented by supplying these critical nutrients of a vegan diet adequately. A purely plant-based diet can provide all necessary macro- and micronutrients during pregnancy and childhood, except DHA and EPA, as well as vitamin B12. Newborns of vegan mothers are smaller (small for gestational age) and are born with a lower birth weight than those born from omnivores, which can lead to further nutrient-deficiency-related development and health consequences. If the mother lacks an adequate supply of nutrients, nutrient deficiencies can occur in the infant despite breastfeeding. Expert groups such as the Academy of Nutrition and Dietetics (AND) and German Society for Nutrition (DGE) disagree about the risks of a purely plant-based diet for pregnant women, infants and children. In the past no distinct statements were made on the benefits or drawbacks for vegan pregnant women and their children in terms of nutrient supply, due to a lack of well-designed studies. Latest findings show that there are risks of malnutrition, which can be prevented by dietary supplements and observing the health and developmental status of mother and child. Although the selection of vegan foods is becoming more diverse, there is no data on whether this expansion of the offer results in a better nutrient supply for vegans - the current state of studies suggests dietary supplementation is necessary. Pregnant women who consume an omnivorous diet are often taking dietary supplements to support the healthy development of their unborn children. Influencing factors that affect the approach of vegan pregnant women and parents towards dietary supplements have not yet been scientifically determined. It has been shown that mothers who feed their children a vegan diet have less nutritional knowledge than mothers whose children follow an ovo-lacto-vegetarian diet. Parents often ask pediatricians how to provide the most balanced diet for their children. For this reason, constructive communication between parents of vegan children and their pediatricians and dieticians is important in order to provide comprehensive information about a healthy, purely plant-based diet. The relationship between vegan parents and doctors can therefore influence the health and well-being of vegan children. However, the majority of pediatricians is perceived skeptical or negative towards a vegan diet, which can affect vegan parents' trust in their children's doctors and limit or prevent communication. Many parents don't inform pediatricians about their children's vegan diet in order not to be exposed to criticism. The skeptical attitude of doctors could result from legitimate, nutrition-related objections on the one hand and from a lack of knowledge about a vegan diet and dietary supplements on the other. This can lead to health consequences for vegan pregnant women and children due to a lack of information supply and miscommunication. It is not yet clear whether other specialists and medical experts in addition to pediatricians have a negative attitude towards a vegan diet during pregnancy and childhood and therefore offer little or no advice on vegan diets and dietary supplements. If a negative attitude also exists among gynecologists, general practitioners, dieticians and pharmacists, this could have a negative effect on vegans due to a lack of information transfer. The level of information and the associated information provided by medical experts on a vegan diet and dietary supplements during pregnancy and childhood therefore has a significant impact on the adequate nutrient supply of metioned vegans. The level of knowledge among medical experts regarding a vegan diet and dietary supplements has not yet been sufficiently examined. Competent advice on supplementation with dietary supplements is essential for a healthy development during pregnancy and childhood. If information is not provided by medical experts, vegans use other sources of information. It can be assumed that many vegans are insufficiently, incorrectly or not at all informed about dietary supplements and a well-balanced vegan diet due to the different quality of provided information. Dubious sources of information and external influencing factors (social environment, Internet and Social Media, magazines, advertisement etc.) are likely to make parents feel insecure and can affect the health of their children. A lack of expertise on the part of vegan pregnant women and parents (on a vegan diet and dietary supplements) and insufficient support from medical experts (paediatricians, gynaecologists, general practitioners, pharmacists, dieticians) entails possible health risks. The impact of medical expertise and other social, sociodemographic factors (age, social environment and background, Internet and Social Media, advertising etc.), on the diet of vegan pregnant women and children (up to an age of 5 years), as well as on supplementation with dietary supplements needs to be researched. Whether and to what extent external factors influence a vegan pregnancy, infancy and childhood has not yet been scientifically investigated. In addition, there is still no data on the opinion and level of knowledge of consulting medical experts and associated consequences regarding nutrition and the possibility of supplementing dietary supplements for vegans. Results may demonstrate the need for comprehensive counseling on dietary supplements and a vegan diet and highlight the need for better and competent information provision by medical experts to pregnant vegan women and parents of vegan children.