Many mothers experience raised blood pressure it seems. Is this due to our busy lifestyles, more mums giving birth at an older age? Who knows but it causes a lot of confusion. The drug normally initiated if a mother has symptoms of pre-eclampsia is labetolol. It is usually continued after delivery until the BP has settled. Virtually none passes into breastmilk. However, some mothers with poor circulation may notice sore, white nipples where the supply to the tip is decreased . If this happens the drug may need to be changed. Prolonged high BP in pregnancy can lead to restricted growth of the baby who may be born sleepy. Rather than just monitoring blood glucose levels the baby should be helped to attach to the breast and feed regularly or be given colostrum by spoon or syringe. A drop of colostrum can work magic.
Later blood pressure rises can be treated with enalapril, amlodipine and felodipine which are all compatible with breastfeeding according to expert sources. The NICE Guidelines NG 133 (2019) can also guide good practice.
The data for this fact sheet is taken from my book Breastfeeding and Medication which provides more detail and references to studies. Please consider buying a copy for future reference.