Oxytocin is a hormone produced by the pituitary gland in the brain. It increases relaxation, lowers stress and anxiety, lowers blood pressure, and causes muscle contractions. Oxytocin, also called the mothering, cuddle or love hormone, is involved in social relationships, bonding, trust, and love. Breastfeeding stimulates the release of oxytocin from your brain. When your baby latches on to breastfeed, the nerve cells in your breasts send a signal to your brain to release oxytocin. The oxytocin causes the muscles around the milk-making glands in your breast to contract, squeezing the breast milk into the milk ducts. The milk ducts then contract to push the breast milk through your breast, out of the nipple to your baby. This is called the let-down reflex. As baby continues to breastfeed, more oxytocin is released and milk continues to flow. You may experience 2-14 let-downs in one breastfeeding session! The release of oxytocin while you're breastfeeding may make you feel sleepy and relaxed. It can raise your body temperature and is one of the reasons you may feel so hot while nursing. It might also make you feel thirsty or even give you a headache!
Oxytocin can cause your milk to let-down when you're not breastfeeding. Hearing a baby cry, thinking about your baby or even smelling something that reminds you of your baby can trigger oxytocin flow and make you leak!! While oxytocin is responsible for the let-down reflex and the release of breast milk from your body, it has nothing to do with the amount of breast milk that you will make. Prolactin is the hormone that does that.
Some people feel the oxytocin release (aka Let-Down) and others don’t. Both are totally normal!
Signs of let down include:
- Tingling or a pins-and-needles sensation in your breasts. It could be a light sensation or even an electrical shock feeling.
- Hearing baby swallow while at the breast.
- Leaking milk from the other breast
- Uterine cramps when breastfeeding, especially the first week.
- Feeling happy and relaxed after you feed your baby.
Factors that inhibit oxytocin release and let down include: pain, breast surgery or trauma, stress, illness, fatigue, fear, embarrassment, drinking or smoking.
Some mothers may breastfeed and let-down milk just fine to baby but struggle to release milk to an electric pump. A quality double electric breast pump will have two modes: a quick cycle/light suction or "stimulation" mode, and a slow cycle, hard suction of "expression" mode. By alternating several times between these modes in a pump session, you can trick your body into thinking baby is feeding to stimulate more let-downs of milk. When pumping, you can also help stimulate your body to let-down more often by:
- Watching videos or looking at pictures of your baby
- Smelling something that reminds you of your baby (a onesie, your baby shampoo or soap, lavender)
- Listening to calming music
- Using heat before and during pumping
- Massaging your breasts before and during pumping
- Eating a snack or drinking water while pumping