The let-down reflex is an important part of breastfeeding that starts milk flowing when your baby feeds. Each woman feels it differently, and some may not feel it at all. It can be affected by stress, pain and tiredness but once feeding is established, it requires little or no thought.

What is the let-down reflex?

The let-down reflex is what makes breastmilk flow. When your baby sucks at the breast, tiny nerves are stimulated. This causes two hormones – prolactin and oxytocin – to be released into your bloodstream. Prolactin helps make the milk, while oxytocin causes the breast to push out the milk. Milk is then released or let down through the nipple.

Some women feel the let-down reflex as a tingling sensation in the breasts or a feeling of fullness, although others don’t feel anything in the breast.

Most women notice a change in their baby’s sucking pattern as the milk begins to flow, from small, shallow sucks to stronger, slower sucks.

Some women also notice, while feeding or expressing from one breast, that milk drips from the other.

Your let-down reflex needs to be established and maintained to ensure a good supply of milk. This reflex requires no thought, unless you are having problems with breastfeeding.

When does it occur?

The let-down reflex occurs:

• in response to your baby sucking at the breast
• hearing, seeing or thinking about your baby
• using a breast pump, hand expressing or touching your breasts or nipples
• looking at a picture of your baby
• hearing your baby (or another baby) cry

The let-down reflex generally occurs 2 or 3 times a feed. Most women only feel the first, if at all. This reflex is not always consistent, particularly early on, but after a few weeks of regular breastfeeding or expressing, it becomes an automatic response.

The let-down reflex can also occur with other stimulation of the breast, such as by your partner.

Strategies to encourage the reflex

The let-down reflex can be affected by stress, pain and tiredness. There are many things to try if you are experiencing difficulty.

• Ensure that your baby is correctly attached to the breast. A well-attached baby will drain a breast better.
• Feed or express in a familiar and comfortable environment.
• Try different methods to help you to relax: calming music, a warm shower or a warm washer on the breast, some slow deep breathing, or a neck and shoulder massage.
• Gently hand express and massage your breast before commencing the feed.
• Look at and think about your baby.
• If you are away from your baby, try looking at your baby’s photo.
• Always have a glass of water nearby.

Milk let-down can be quite forceful, particularly at the beginning of a feed. This fast flow of milk can upset your baby, but it might not mean you have oversupply. It can be managed through expressing before a feed, reclining slightly and burping your baby after the first few minutes. If you continue to have problems, seek advice.

How to deal with unexpected let-down

Until you and your baby fine-tune breastfeeding, many sensations and thoughts can trigger your let-down reflex. Leaking breasts can be embarrassing, but should stop once breastfeeding is fully established.

In the meantime you can feed regularly, apply firm pressure to your breasts when you feel the first sensation of let-down, use breast pads and wear clothing that disguises milk stains.

If you need help and advice:

• Pregnancy Birth and Baby on 1800 882 436
• your maternal child health nurse
• a lactation consultant (your maternity hospital might be able to help)
• Australian Breastfeeding Association on 1800 686 268