Pregnant women do not need to eat for two, but they should eat well. During pregnancy, they will have slightly higher nutritional needs in order to stay healthy during gestation and prepare for breastfeeding. For most women, these higher needs can be met by two to three additional servings from any food group in Canada's Food Guide.
For example, two portions would be 1 fruit and 175 g (¾ cup) of yogurt, and three portions would be equivalent to 1 slice of whole grain bread (35 g) with 50 g (1½ oz) of cheese and 125 ml (½ cup) of orange juice.
Additional portions can either be eaten as snack or added to regular meals. Pregnant women should make an effort to eat three meals a day plus healthy snacks, and drink water during the day.
During gestation, it is important for mothers-to-be to eat foods from all Canada's Food Guide groups. Choose colourful fruits and vegetables because they contain more vitamins.
In terms of grain products, it is preferable to eat "whole grain" foods.
Milk and milk substitutes are essential for fetal growth; pregnant women should consume the equivalent of two glasses of milk or fortified soy beverage every day. Finally, eat meat or meat substitutes every day, and if you eat fish, be sure to choose fish with low mercury content.
In addition to a healthy diet, Health Canada generally recommends that pregnant women take a daily multivitamin containing iron plus folic acid, to ensure that mother and baby both get everything they need for a healthy pregnancy.
Health Canada, From Tiny Tot to Toddler