Anatomy & Physiology of Lactation Flashcards

Lactogenesis II is defined as the onset of copious milk secretion. When does it typically occur?

Answer: Between 30 and 72 hours postpartum

Lactogenesis II, triggered by the drop in progesterone after placental delivery and sustained prolactin, typically results in milk 'coming in' between 30–72 hours postpartum.

Which stage of lactation describes the secretory differentiation of mammary epithelial cells that begins mid-pregnancy?

Answer: Lactogenesis I

Lactogenesis I (secretory differentiation) occurs around mid-pregnancy when alveolar cells differentiate into secretory lactocytes capable of producing small amounts of colostrum.

What distinguishes colostrum from mature breast milk in terms of protein content?

Answer: Colostrum has higher protein concentration than mature milk

Colostrum is concentrated with protein (especially secretory IgA, lactoferrin, and growth factors) at roughly 2–3 times the protein concentration of mature milk.

Galactopoiesis refers to which phase of lactation?

Answer: Ongoing maintenance of established milk supply

Galactopoiesis (also called Lactogenesis III) describes the autocrine-driven maintenance of milk supply that depends on frequent and effective milk removal.

The Feedback Inhibitor of Lactation (FIL) regulates milk supply through which mechanism?

Answer: It is a whey protein in accumulated milk that suppresses further secretion locally

FIL is a whey protein produced in the alveoli that accumulates when milk is not removed, signaling lactocytes to slow production via autocrine control.

What is the primary carbohydrate in human breast milk and what function does it serve?

Answer: Lactose; provides energy and promotes beneficial gut bacteria

Lactose is the predominant carbohydrate in human milk; it provides energy and is partially converted to galactose, which supports brain development and promotes Lactobacillus growth.

Which component of breast milk is highest in hindmilk compared to foremilk?

Answer: Fat

Fat content increases progressively within a feeding as milk is ejected from the alveoli, making hindmilk fat-rich compared to the more watery, lactose-rich foremilk.