If a pregnant woman is thinking about breastfeeding her baby it is helpful for her to have some understanding about the anatomy of the breast and how breastfeeding works. This will enable her to feel more confident about breastfeeding and to trust her body's ability to provide milk for her baby.

The non-pregnant breast is largely made up of fat and it is during pregnancy that the milk producing glands increase in size and a redistribution of the fat occurs. The milk producing tissue is divided into fifteen to twenty lobes in each breast. Each lobe of the breast resembles the leaves, branches and trunk of a tree. Every lobe has the glandular tissue and branching milk ducts which ultimately open at the nipple. The glandular tissue is made up of the alveoli which look rather like a bunch of grapes. The alveoli secrete and store milk until it is ejected out of the breast. Behind the nipple each duct widens to form a kind of reservoir, the ampulla.

From about the third month of pregnancy the breast begins to produce colostrum which is the first milk that flows after the baby's birth and up until approximately the tenth day. Progesterone which is present in large amounts during the pregnancy, prevents the breasts from producing the mature milk through inhibiting the action of prolactin, the milk producing hormone.

After the birth of the baby and the expulsion of the placenta the progesterone levels in the mother's body decrease substantially and the prolactin released by the anterior pituitary can then begin to take effect and cause the milk glands to secrete milk. At this stage the mature milk is produced. The next step is that the milk has to be made available to the baby. When the baby is put to the breast, the stimulation to the nipple causes the release of oxytocin from the posterior pituitary which results in the contraction of the little muscles around the alveoli. The contraction of these little muscles causes the milk to be squeezed and propelled down the ducts and to be made available to the baby. This is called the let down reflex and to a greater or lesser degree the milk will leak or drip from the nipple. The baby at the breast then obtains the milk through a milking action by its tongue and jaw.

The let down reflex may be felt as a tingling sensation inside the breast or the mother may be aware of it by the sound of the contented gulps from the baby as he drinks the milk.

The above is an outline on how breastfeeding works and articles will follow that explain how to position the baby at the breast.