Deal Breastfeeding Support Group

How do my breasts make milk?

The breasts are specially designed for making milk; their size is unrelated to how much milk they can produce. The areola is the darker area around the nipple which contains small glands called Montgomery's glands. These secrete an oily fluid to keep the skin healthy. This oily fluid is what your baby will smell and this helps the baby to recognise you.

Breast AnatomyThe Breast: cross-section scheme of the mammary gland.
1. Chest wall
2. Pectoralis muscles
3. Lobules
4. Nipple
5. Areola
6. Milk duct
7. Fatty tissue
8. Skin

Source Wikipedia

Inside the breasts there are about 20 lobes of glandular tissue surrounded by supportive tissue. The fat and supportive tissue gives your breasts their shape and size and what makes our breasts different sizes. The lobes contain alveoli (very small sacs of milk-secreting cells) they are clustered together in microscopic grape-like bunches emptying into a ductal system. A hormone called prolactin makes these cells produce milk. Around the alveoli there are networks of muscle cells which contract and make the milk flow. The hormone oxytocin makes these muscle cells contract. This is what causes the let-down reflex. Oxytocin is produced before and during a feed. (It is this hormone that makes the uterus contract after delivery. This helps to reduce bleeding but can cause slight pain and a rush of blood during a feed in the first few days.)

The milk comes out of the nipple through about 15 small openings in your nipple. When your baby is latched on, they stimulate the areola, which send sensory impulses from the nipple to the brain. Prolactin from the pituitary gland goes into the blood to the breast. The milk-secreting glands then produce milk. More prolactin is produced at night, therefore feeding during the night is important for keeping up the milk supply. The prolactin levels remain high for about 90 minutes after the feed and this makes the breast produce milk for the next feed. So, if the baby suckles more, the mother’s breasts will make more milk. Prolactin makes the mother feel relaxed and sleepy, so getting back to sleep after a feed may be easier if breastfeeding.

Video of a Feed