Medela Calma Breast Milk Bottle 150ml. Medela Calmabreast milk bottle is an alternative to breastfeeding for mothers who want to feed the baby by breast milk but cannot breastfeed. The baby's sucking reflexes are retained by using the Calma feeding bottle and the optional attachment. The Calma teat is ideal if a mom wants to resume breastfeeding as Calma allows natural switching between breast and bottle. The silicone teat is soft and flexible, the baby can breathe, swallow and relax. Milk flow stops when the baby is breathing or takes a break.