In healthy women on a normal diet, advice on eating five portions of fruit and vegetables per day and consuming dairy products to raise stores of vitamins, iron and calcium is reasonable.
Because of the dangers of toxoplasmosis and listeriosis, women should avoid:
• Uncooked meat, fish and eggs
• Unpasteurised milk
• Unripened soft cheeses, such as Brie, Camembert or blue-veined cheese
• Unwashed fruit and vegetables
Vegetarians, and especially vegans, are at risk of various nutritional deficiencies and may need to be referred to a dietitian.
Vitamin D deficiency causes impaired fetal growth. All women should be informed about the importance of maintaining adequate vitamin D stores during pregnancy and breast-feeding.
Caffeine during pregnancy may cause fetal growth restriction. One cohort study found an odds ratio of 1.2 for 100-199 mg of caffeine/day (1-2 cups of coffee, 2-4 cups of tea) and 1.6 for >300 mg caffeine/day (more than 3 cups of coffee or 6 cups of tea). A sensible approach would be to reduce caffeine consumption prior to pregnancy in heavy users.
Women should be cautioned, however, against substituting caffeinated drinks with herbal preparations and teas, as their use and safety in pregnancy have not been studied.