You can do SW while trying to get pregnant, throughout your pregancy and post-birth even while breastfeeding as it's a balanced, healthy diet and just what you need. While pregnant you need to get a permission slip from your midwife saying it's okay. You don't get any extras until after the birth and then only if you breast feed. You would get more HEs, the number depending on the age of the baby and whether you are breastfeeding exclusively or weaning.