CBS Lactation Physiology & Nutrition 2 — Questions and Answers
Question 1: Which hormone is primarily responsible for milk ejection (let-down reflex) during breastfeeding?
- Prolactin
- Oxytocin (Correct answer)
- Estrogen
- Progesterone
Correct answer: Oxytocin
Oxytocin is released from the posterior pituitary and causes myoepithelial cells around alveoli to contract, ejecting milk into the ducts.
Question 2: Which fatty acid found in human breast milk is critical for infant brain and retinal development?
- Linoleic acid
- Alpha-linolenic acid
- Docosahexaenoic acid (DHA) (Correct answer)
- Eicosapentaenoic acid (EPA)
Correct answer: Docosahexaenoic acid (DHA)
DHA is an omega-3 long-chain polyunsaturated fatty acid essential for neural and retinal development in infants.
Question 3: Foremilk differs from hindmilk primarily in its:
- Protein content
- Fat content (Correct answer)
- Lactose concentration
- Immunoglobulin levels
Correct answer: Fat content
Hindmilk has a higher fat content than foremilk, which is more watery and lower in fat but similar in protein and lactose.
Question 4: A breastfeeding mother asks about Vitamin D supplementation. Current AAP guidelines recommend daily Vitamin D supplementation of how many IU for exclusively breastfed infants?
- 200 IU
- 400 IU (Correct answer)
- 600 IU
- 1000 IU
Correct answer: 400 IU
The AAP recommends 400 IU of Vitamin D daily for all breastfed infants starting within the first few days of life.
Question 5: The primary carbohydrate in human breast milk that promotes growth of Lactobacillus bifidus is:
- Sucrose
- Glucose
- Lactose
- Human milk oligosaccharides (HMOs) (Correct answer)
Correct answer: Human milk oligosaccharides (HMOs)
Human milk oligosaccharides serve as prebiotics that selectively promote growth of beneficial bifidobacteria in the infant gut.
Question 6: During pregnancy, which hormone suppresses milk secretion despite rising prolactin levels?
- Cortisol
- Progesterone (Correct answer)
- Human chorionic gonadotropin
- Thyroid-stimulating hormone
Correct answer: Progesterone
High progesterone levels during pregnancy inhibit prolactin's ability to stimulate milk synthesis at the alveolar receptor level.
Question 7: Which immunoglobulin is most abundant in human colostrum and provides passive mucosal immunity to the newborn?
- IgG
- IgM
- IgA (secretory) (Correct answer)
- IgE
Correct answer: IgA (secretory)
Secretory IgA (sIgA) is the predominant immunoglobulin in colostrum and mature milk, protecting infant mucosal surfaces against pathogens.
CBS Lactation Physiology & Nutrition 2
Which hormone is primarily responsible for milk ejection (let-down reflex) during breastfeeding?