CBS Lactation Physiology & Nutrition 3 — Questions and Answers
Question 1: Galactopoiesis refers to:
- The initiation of lactation at birth
- The maintenance of established milk production (Correct answer)
- The cessation of milk production
- The composition changes in transitional milk
Correct answer: The maintenance of established milk production
Galactopoiesis is the ongoing maintenance of milk production after it has been established, dependent on continued suckling and prolactin release.
Question 2: Feedback Inhibitor of Lactation (FIL) is a whey protein that:
- Stimulates milk production when milk is removed
- Decreases milk synthesis when milk accumulates in the breast (Correct answer)
- Increases fat content in hindmilk
- Triggers the let-down reflex
Correct answer: Decreases milk synthesis when milk accumulates in the breast
FIL is a local autocrine inhibitor that slows milk synthesis when milk accumulates in the alveoli, preventing engorgement injury.
Question 3: A lactating mother follows a strict vegan diet. Her exclusively breastfed infant is at highest risk for deficiency of which nutrient?
- Vitamin C
- Iron
- Vitamin B12 (Correct answer)
- Calcium
Correct answer: Vitamin B12
Vitamin B12 is found almost exclusively in animal products; vegan mothers have low B12 in milk, putting their infants at risk for deficiency and neurological damage.
Question 4: The alveoli in the mammary gland are lined primarily with:
- Myoepithelial cells
- Lactocytes (secretory epithelial cells) (Correct answer)
- Adipocytes
- Stromal fibroblasts
Correct answer: Lactocytes (secretory epithelial cells)
Lactocytes are the secretory epithelial cells that synthesize and secrete milk components into the alveolar lumen.
Question 5: Which statement about iron in human breast milk is accurate?
- Human milk contains high levels of iron to meet infant needs
- Iron in human milk has low bioavailability compared to formula
- Iron in human milk is highly bioavailable (approximately 50%) due to lactoferrin (Correct answer)
- Iron supplementation is needed from birth for all breastfed infants
Correct answer: Iron in human milk is highly bioavailable (approximately 50%) due to lactoferrin
Although human milk contains relatively low iron concentrations, its bioavailability is approximately 50% due to lactoferrin and other binding proteins, compared to only 4-7% from formula.
Question 6: Prolactin levels are highest:
- Immediately before a feeding
- During active suckling and for 30-45 minutes after (Correct answer)
- 24 hours after delivery
- Only during the first week postpartum
Correct answer: During active suckling and for 30-45 minutes after
Prolactin surges during suckling and remains elevated for 30-45 minutes afterward, stimulating milk synthesis for the next feeding.
Question 7: Which electrolyte in breast milk increases significantly when mastitis or breast inflammation is present?
- Potassium
- Sodium (Correct answer)
- Calcium
- Phosphorus
Correct answer: Sodium
Sodium concentration in breast milk rises during mastitis or significant inflammation because tight junctions between lactocytes open, allowing paracellular leakage.
