The Hormone Heroes of Breastfeeding
While pregnant, you don’t have to think about what is happening; your body knows what to do and grows the baby without your mind having to do much! Once your baby arrives, your body is similarly primed and ready to sustain your new little one by producing milk. Maintaining a strong milk supply takes a bit more conscious thought than pregnancy, and understanding how lactation works can help you ensure nursing success. As an International Board Certified Lactation Consultant, I love teaching parents prenatally!
There are two essential hormones that orchestrate the production and delivery of breast milk: prolactin and oxytocin. Prolactin is the primary hormone in charge of milk supply. After delivery of your baby and placenta, prolactin levels surge, promoting milk production. Your mature milk “comes in” 3-5 days after delivery, which means it increases in volume and changes composition for the first of many times. (Did you know that breast milk changes in composition as your nursling grows to meet baby's developmental needs? It is truly amazing!) The stimulation of your baby feeding sends messages to your brain, signaling demand for more milk. More prolactin is released, which in turn tells your milk glands to maintain and/or increase production. For pumping parents, your pump serves as a substitute for baby: the stimulation and expression from the pump also helps maintain supply.
After childbirth, oxytocin is also released from the brain, causing your uterus to contract and gradually shrink back down to normal size and reduce bleeding from the detachment of the placenta. In addition, oxytocin is responsible for “letdown,” when milk glands contract and milk rushes down and out. As baby nurses, more signals are sent out and more oxytocin is released. Not only does oxytocin move milk, it also promotes feelings of bonding, protectiveness, and care in new parents! Nicknamed “the love hormone,” oxytocin can feel euphoric and flood a new mother with affection and peace, physically lowering blood pressure and anxiety.
It is important to recognize that all these systems can be gummed up by outside forces, and we should be aware of things that can interfere with the release of prolactin and oxytocin while nursing. Certain types of birth control that contain estrogen can hinder prolactin release, resulting in milk decline. And, because prolactin and oxytocin rely on the stimulation of breastfeeding, introducing a pacifier too early can decrease the number of signals your brain receives and cause low supply. Similarly, scheduled feeds and/or sleep training can also have negative effects on milk supply. Depression can be a factor in low prolactin and oxytocin levels, as well.
In the early weeks of breastfeeding, be mindful to nurse frequently, every 2-3 hours around the clock. Resting when you can, staying hydrated, and eating nutrient-rich foods such as leafy greens and whole grains can also help keep these systems running smoothly. And finally, skin-to-skin contact is fantastic for oxytocin release, so snuggle that new little one as much as you like! It’s wonderful for both of you.
Jennifer Hafele is active in the Chippewa Valley birth and postpartum care community. She provides professional lactation support through her private practice, Mama Bear Lactation Care. Offering a free support group is a cornerstone of her practice. She also loves co-teaching “Confident Birth & Beyond,” an independent childbirth and postpartum education series. Connect with Jennifer on Facebook or at MamaBearLactationCare.com.