ALPP Certified Lactation Counselor
(CLC) Exam Prep: 150 Practice
Questions with Detailed Rationales |
Fall 2025/2026 Updated
DOMAIN 1: LACTATION PHYSIOLOGY & HORMONES (Questions 1-25)
Question 1
A lactating mother reports a painful, reddened area on her right breast with
no systemic symptoms. Upon palpation, you feel a firm, tender nodule.
What is the MOST likely diagnosis?
A) Inflammatory breast cancer
B) Plugged milk duct
C) Mastitis
D) Breast abscess
Correct Answer: B) Plugged milk duct
Rationale: A plugged duct presents as a localized, tender lump without
systemic symptoms (fever, malaise). Mastitis would include systemic
symptoms such as fever and malaise. Inflammatory breast cancer is rare
and not typically associated with lactation. An abscess would be fluctuant
and often follows untreated mastitis.
,Question 2
Which hormone is primarily responsible for the "milk ejection reflex" (let-
down)?
A) Prolactin
B) Estrogen
C) Oxytocin
D) Progesterone
Correct Answer: C) Oxytocin
Rationale: Oxytocin is responsible for the milk ejection reflex (let-down). It
causes the myoepithelial cells surrounding the alveoli to contract, ejecting
milk into the ducts. Prolactin is responsible for milk synthesis, while
estrogen and progesterone play roles in breast development and
pregnancy maintenance.
Question 3
Which hormone is primarily responsible for milk synthesis (production) in
the mammary glands?
A) Oxytocin
B) Prolactin
C) Estrogen
D) Progesterone
Correct Answer: B) Prolactin
Rationale: Prolactin is the primary hormone responsible for milk synthesis
(lactogenesis). It is secreted by the anterior pituitary gland and stimulates
,the alveolar cells to produce milk. Oxytocin is responsible for milk ejection,
not synthesis.
Question 4
Lactogenesis I refers to:
A) The onset of copious milk production after delivery
B) Secretory differentiation during pregnancy
C) The maintenance of established milk production
D) The cessation of milk production
Correct Answer: B) Secretory differentiation during pregnancy
Rationale: Lactogenesis I is secretory differentiation that occurs during the
second half of pregnancy. The mammary glands become capable of
producing colostrum, but high levels of progesterone inhibit full milk
production.
Question 5
Lactogenesis II refers to:
A) Secretory differentiation during pregnancy
B) The onset of copious milk production 30-72 hours after delivery
C) The maintenance of established milk production
D) The cessation of milk production
Correct Answer: B) The onset of copious milk production 30-72 hours
after delivery
, Rationale: Lactogenesis II is the onset of copious milk production, typically
occurring 30-72 hours after delivery. This stage is triggered by the sudden
drop in progesterone following delivery of the placenta.
Question 6
Which of the following is the PRIMARY carbohydrate found in human milk?
A) Sucrose
B) Glucose
C) Lactose
D) Maltose
Correct Answer: C) Lactose
Rationale: Lactose is the primary carbohydrate found in mammalian milk,
including human milk. It is a disaccharide composed of glucose and
galactose and provides approximately 40% of the calories in human milk.
Question 7
Prolactin levels are highest during which time?
A) Immediately before feeding
B) During feeding
C) Immediately after feeding
D) During sleep
Correct Answer: D) During sleep
(CLC) Exam Prep: 150 Practice
Questions with Detailed Rationales |
Fall 2025/2026 Updated
DOMAIN 1: LACTATION PHYSIOLOGY & HORMONES (Questions 1-25)
Question 1
A lactating mother reports a painful, reddened area on her right breast with
no systemic symptoms. Upon palpation, you feel a firm, tender nodule.
What is the MOST likely diagnosis?
A) Inflammatory breast cancer
B) Plugged milk duct
C) Mastitis
D) Breast abscess
Correct Answer: B) Plugged milk duct
Rationale: A plugged duct presents as a localized, tender lump without
systemic symptoms (fever, malaise). Mastitis would include systemic
symptoms such as fever and malaise. Inflammatory breast cancer is rare
and not typically associated with lactation. An abscess would be fluctuant
and often follows untreated mastitis.
,Question 2
Which hormone is primarily responsible for the "milk ejection reflex" (let-
down)?
A) Prolactin
B) Estrogen
C) Oxytocin
D) Progesterone
Correct Answer: C) Oxytocin
Rationale: Oxytocin is responsible for the milk ejection reflex (let-down). It
causes the myoepithelial cells surrounding the alveoli to contract, ejecting
milk into the ducts. Prolactin is responsible for milk synthesis, while
estrogen and progesterone play roles in breast development and
pregnancy maintenance.
Question 3
Which hormone is primarily responsible for milk synthesis (production) in
the mammary glands?
A) Oxytocin
B) Prolactin
C) Estrogen
D) Progesterone
Correct Answer: B) Prolactin
Rationale: Prolactin is the primary hormone responsible for milk synthesis
(lactogenesis). It is secreted by the anterior pituitary gland and stimulates
,the alveolar cells to produce milk. Oxytocin is responsible for milk ejection,
not synthesis.
Question 4
Lactogenesis I refers to:
A) The onset of copious milk production after delivery
B) Secretory differentiation during pregnancy
C) The maintenance of established milk production
D) The cessation of milk production
Correct Answer: B) Secretory differentiation during pregnancy
Rationale: Lactogenesis I is secretory differentiation that occurs during the
second half of pregnancy. The mammary glands become capable of
producing colostrum, but high levels of progesterone inhibit full milk
production.
Question 5
Lactogenesis II refers to:
A) Secretory differentiation during pregnancy
B) The onset of copious milk production 30-72 hours after delivery
C) The maintenance of established milk production
D) The cessation of milk production
Correct Answer: B) The onset of copious milk production 30-72 hours
after delivery
, Rationale: Lactogenesis II is the onset of copious milk production, typically
occurring 30-72 hours after delivery. This stage is triggered by the sudden
drop in progesterone following delivery of the placenta.
Question 6
Which of the following is the PRIMARY carbohydrate found in human milk?
A) Sucrose
B) Glucose
C) Lactose
D) Maltose
Correct Answer: C) Lactose
Rationale: Lactose is the primary carbohydrate found in mammalian milk,
including human milk. It is a disaccharide composed of glucose and
galactose and provides approximately 40% of the calories in human milk.
Question 7
Prolactin levels are highest during which time?
A) Immediately before feeding
B) During feeding
C) Immediately after feeding
D) During sleep
Correct Answer: D) During sleep
