Breast Anatomy and notes
Development of the breast can proceed through a number of lactation cycles (pregnancy, lactogenesis I, lactogenesis II, and involution.
- occurs in the latter stage of pregnancy.
- The breast produces thick yellow colostrum
- at this stage high progesterone levels inhibit milk production
- at or soon after birth progesterone levels drop and prolactin levels remain high
- This results in milk production
- When the breast is stimulated, prolactin levels in the blood rise, peak in about 45 minutes, and return to the pre-breastfeeding state about three hours later.
- The release of prolactin triggers the cells in the alveoli to make milk. Prolactin also transfers to the breast milk
- Lactogenesis I and II are under hormonal endocrine control during pregnancy and for the first few days following birth
- When milk production is established, it switches from endocrine to autocrine control (lactogenesis III)
- During this stage, the more that milk is removed from the breasts, the more the breast will produce milk.
- Draining the breasts more fully also increases the rate of milk production.
- Milk supply is strongly influenced by how often the baby feeds and how well it is able to transfer milk from the breast.
Low supply can often be traced to:
- not feeding or pumping often enough
- inability of the infant to transfer milk effectively caused by, among other things:
- jaw or mouth structure deficits
- poor latching technique
- rare maternal endocrine disorders
- hypoplastic breast tissue
- a metabolic or digestive inability in the infant, making it unable to digest the milk it receives
- inadequate calorie intake or malnutrition of the mother