Dina Aronson, MS, RD is a vegan dietitian whose specialties include chronic disease prevention, vegetarian/vegan nutrition, and lifestyle management. She is the founder and director of VeganRD.com, a nutrition consulting company. Active in many vegetarian nutrition organizations, Dina was the recipient of the American Dietetic Association's Recognized Young Dietitian of the Year Award in 2002.
Is it ok to switch over to a vegan diet during pregnancy?
Yes, as long as the diet is meeting the needs for the baby's growth and development. A pregnant woman who becomes vegan needs to be educated about a healthy vegan diet before and during the switch. I recommend a consultation with a registered dietitian or licensed nutritionist specializing in vegan diets.
An change from one diet to another usually comes with a change in calorie and nutrient levels, so it is important to be sure that the diet follows pregnancy guidelines for calorie, protein, fat, vitamin, mineral, and fluid requirements. For a more detailed discussion of these guidelines, see this article: Advice for Vegan Mothers-to-Be - Nine Months of Proper Nutrition.
Obviously, going from a meat- and cheese-centered diet to a vegan one overnight might be particularly challenging, while going from a largely plant-based diet with a few animal products to a vegan one might be quite simple. Either way, the woman should be well-educated and follow guidelines for a healthy vegan pregnancy.