This article gathers the current knowledge base around veganism and plant-based diets in pregnancy and infant feeding, to explore how midwives can better support the increasing numbers of women and families who are embracing a plant-based lifestyle. People who identify as vegan are becoming increasingly common. There has also been an increase in ‘flexitarianism’ and those adopting plant-based diets for health and/or environmental reasons. There is a need to consolidate the nutritional guidance, to enable better and more consistent evidence-based support for these groups.