The let-down reflex (milk ejection reflex)
- By sucking at the breast, your baby triggers tiny nerves in the nipple.
- These nerves cause hormones to be released into your bloodstream.
- One of these hormones (prolactin) acts on the milk-making tissues.
- The other hormone (oxytocin) causes the breast to push out or ‘let down’ the milk.
- The let-down reflex makes the milk in your breasts available to your baby.
- Cells around the alveoli contract and squeeze out the milk, pushing it down the ducts towards the nipple.
- Oxytocin also makes the milk ducts widen, making it easier for the milk to flow down them.
- The let-down may happen if you see or hear your baby or even just think about them.
- The let-down can also be triggered by touching your breast and nipple area with your fingers or by using a breast pump.
- People often say that your milk supply can be impacted if you are very anxious, extremely tired, upset or in pain. The truth is that breastfeeding is a powerful process. Usually your supply won't be impacted by these factors but it is possible that the let-down may be impacted or take a little longer than usual, causing your baby to fuss at the breast or come on and off. There are ways you can help your let-down to occur (see below).
You may be aware of the let-down as:
- a tingling feeling, which can be quite strong
- a feeling of sudden fullness
- milk dripping from the other breast
- a change in the baby’s sucking pattern from a quick suck-suck to a rhythmic suck-swallow pattern as the milk begins to flow.
In the early days you might feel your uterus contract when you let down, especially if this is not your first baby.
Let-downs usually occur more than once during a feed; however most mothers will only notice the first. These other let-downs occur in response to changes in a baby’s suckling. Some mothers feel the let-down in the early days or weeks, but later find that this feeling goes away.
Ways you can help your let-down to occur when feeding or expressing:
- Relax. While you feed or express, breathe slowly and deeply. Some mothers find it helpful to have a warm drink first or listen to calming music. Warmth may also help, for example having a warm shower or placing a warm face washer on your breast for a few minutes before starting.
- Gently massage your breasts. Stroke your breast towards the nipple with the flat of your hand or edge of a finger. Gently roll your nipple between your fingers.
- Think about your baby. If you are expressing, you may find it easier to express while you are close to your baby. When you are away from your baby, you may find it helpful to look at a photo of your baby.
- Support. Your support person may also help by giving you a gentle back and shoulder massage to help you relax. Some mothers, however, prefer to express or feed in private as they feel under pressure if anyone is watching them.
By sucking at the breast, your baby triggers tiny nerves in the nipple. These nerves cause hormones to be released into your bloodstream. One of these hormones (prolactin) acts on the milk-making tissues. The other hormone (oxytocin) causes the breast to push out or ‘let down’ the milk.
Breastfeeding: an introduction booklet
Breastfeeding: an Introduction provides a basic outline of the key aspects of breastfeeding.
© Australian Breastfeeding Association Reviewed August 2020