• Kolkata, India
  • Email: ankitag2005@gmail.com
  • BLOG
Friday, 20 September 2019 Posted under Breast Feeding

The Different Stages of Lactation

The Different Stages of Lactation

Lactation is a complex process. It starts long before the mother starts to physically suckle her young one and it continues long after. However the term 'Lactation' does not refer to a single function or action but it encompasses a wide of variety events, actions and combinations. Let us discuss these stages:

Mammogenesis refers to the growth and the proliferation of ducts and the glandular system of the breasts, all under the influence of the increased levels of estrogen and progesterone. This visibly manifests in the form of increased mammary (breast) growth, size and weight. This starts at puberty, and the breast goes through mammogenesis during each menstrual cycle till about the age of 30. Post conception there is an increase in mammogenesis.

Lactogenesis refers to the transition from pregnancy to lactation. It is further divided into the following 2 stages:
Lactogenesis I starts from about 16-20 weeks (mid pregnancy) and lasts till about day 2-4 postpartum. Basically it refers to the developing capacity of the mammary glands to secrete milk, from mid pregnancy to late pregnancy. This stage is entirely under the endocrine control which means it is completely under the influence of hormones. At this stage there is a differentiation of the alveolar cells into secretory cells. Prolactin induces the colostrum/milk production. This milk supply is governed by the secretions of hormones and not on the 'supply and demand'.concept
Lactogenesis II refers to the onset of copious milk secretion after birth. It generally starts anywhere between days 2 to 8 postpartum. Initially the milk volume increases rapidly and then suddenly levels off. This is triggered by a sudden drop in the levels of estrogen and progesterone after the expulsion of the placenta. This results in a change of the composition of breast milk. 

Galactopoesis refers to the stage when the milk supply is on maintenance mode. Most women reach this stage by day 10 postpartum. Now the milk production shifts primarily to the autocrine control. This means that only when milk is removed from the breast will more be produced. However there is also some endocrine and metabolic role play, but it is secondary to the autocrine influence.

Involution stage occurs when the breast is no longer being emptied or when the infant has been weaned off from the breast. The breast has stopped receiving receiving any stimulation to produce milk, which results in the glandular tissue of the breast to involute and hence lactation ceases. This process generally takes place about 40 days post the last breastfeeding.