How does breastfeeding work?

Women produce colostrum, the special early milk, from about halfway through pregnancy and for the first few days after birth. Soon after your baby is born, your pregnancy hormones decrease and the milk-producing hormone, prolactin, is produced. Your milk ‘comes in’ after the first few days when colostrum is replaced with milk.

The let-down reflex – making milk available

When your baby starts sucking at your breast, the hormone oxytocin is released, causing the muscle cells around your milk glands to contract and squeeze out breastmilk. This ‘squeezing’ is known as the let-down reflex and this hormone also helps shrink your uterus after birth. Some women feel the let-down reflex as a tingling in the breast but not everyone does. There may be a number of ‘let downs’ every time you breastfeed, and you may or may not be aware of them.

Frequent feeds

Milk production is stimulated by the removal of milk from the breast, i.e. your baby drinking the milk or expressing. Babies have very small stomachs at first and need to feed frequently to build up your milk supply. After a while, baby and breast start to work in harmony, with your milk production matching his needs. Increasing breast milk supply happens naturally in response to increased demand from your baby: the more milk he needs and drinks, the more you make.

Changes in your milk

The fat content of your milk increases as the milk is removed, so when breasts are relatively less full, the fat content is proportionately higher; when your breasts are relatively more full, the fat content is proportionately lower. Healthy, effectively feeding babies will get the right milk intake and type of milk for them. This also means you don’t need to worry about whether your baby is getting a certain amount of ‘foremilk’ (the name given to the lower fat milk) and ‘hind milk’ (the name of the higher fat milk).