CLC Exam Test Bank 2025/2026 | Certified Lactation Counselor Exam Study
Guide & Practice Questions | CLC Certification Exam Prep | Breastfeeding &
Lactation Physiology, Breast Anatomy, Lactogenesis, Prolactin & Oxytocin,
Milk Production & Milk Ejection, Infant Feeding, Latch & Positioning,
Breastfeeding Assessment, Maternal & Infant Health, Common
Breastfeeding Challenges, Engorgement, Mastitis, Sore Nipples, Low Milk
Supply, Pumping & Milk Storage, Prematurity, Infant Nutrition, Counseling &
Communication, Cultural Competence, Ethics, Public Health & Evidence-
Based Lactation Support | Comprehensive Questions & Detailed Rationales
Question 1: Which hormone is primarily responsible for the milk ejection (let-
down) reflex?
A. Progesterone
B. Estrogen
C. Prolactin
D. Oxytocin
E. Cortisol
CORRECT ANSWER: D. Oxytocin
Rationale: Oxytocin triggers the milk ejection reflex by causing myoepithelial cells
surrounding the alveoli to contract, expelling milk into the ducts. Prolactin is
responsible for milk synthesis, while progesterone and estrogen inhibit lactation
during pregnancy.
Question 2: A mother reports painful, cracked nipples that began on day 4
postpartum. The most likely cause is:
A. Oversupply
B. Poor latch
C. Thrush
D. Raynaud's phenomenon
E. Mammary dysbiosis
CORRECT ANSWER: B. Poor latch
Rationale: Poor latch causes nipple trauma through improper positioning, leading
to cracking and pain. Oversupply causes engorgement, thrush involves fungal
infection, and Raynaud's phenomenon causes vasospasm with blanching.
,CLC Exam Test Bank 2025/2026 | Certified Lactation Counselor Exam Study
Guide & Practice Questions | CLC Certification Exam Prep | Breastfeeding &
Lactation Physiology, Breast Anatomy, Lactogenesis, Prolactin & Oxytocin,
Milk Production & Milk Ejection, Infant Feeding, Latch & Positioning,
Breastfeeding Assessment, Maternal & Infant Health, Common
Breastfeeding Challenges, Engorgement, Mastitis, Sore Nipples, Low Milk
Supply, Pumping & Milk Storage, Prematurity, Infant Nutrition, Counseling &
Communication, Cultural Competence, Ethics, Public Health & Evidence-
Based Lactation Support | Comprehensive Questions & Detailed Rationales
Question 3: According to the ALPP Code of Ethics, a CLC must:
A. Promote exclusive formula feeding when requested
B. Respect the mother's informed decision even if it differs from evidence-based
recommendations
C. Refuse to counsel mothers who choose not to breastfeed
D. Share client information with employers without consent
E. Prioritize institutional policies over maternal autonomy
CORRECT ANSWER: B. Respect the mother's informed decision even if it differs
from evidence-based recommendations
Rationale: ALPP ethics emphasize client autonomy and non-judgmental support,
providing information for informed choices. Options A, C, D, and E violate ethical
principles by promoting bias, refusal of care, confidentiality breach, or
institutional overreach.
Question 4: The primary source of energy in mature human milk is:
A. Protein
B. Lactose
C. Fat
D. Oligosaccharides
E. Water
CORRECT ANSWER: C. Fat
Rationale: Fat provides approximately 50% of calories in mature milk, supporting
growth and brain development. Lactose provides about 40%, protein about 10%,
and oligosaccharides are prebiotics rather than primary energy sources.
,CLC Exam Test Bank 2025/2026 | Certified Lactation Counselor Exam Study
Guide & Practice Questions | CLC Certification Exam Prep | Breastfeeding &
Lactation Physiology, Breast Anatomy, Lactogenesis, Prolactin & Oxytocin,
Milk Production & Milk Ejection, Infant Feeding, Latch & Positioning,
Breastfeeding Assessment, Maternal & Infant Health, Common
Breastfeeding Challenges, Engorgement, Mastitis, Sore Nipples, Low Milk
Supply, Pumping & Milk Storage, Prematurity, Infant Nutrition, Counseling &
Communication, Cultural Competence, Ethics, Public Health & Evidence-
Based Lactation Support | Comprehensive Questions & Detailed Rationales
Question 5: A term infant born at 39 weeks should regain birth weight by:
A. 3-5 days
B. 7-10 days
C. 10-14 days
D. 21 days
E. 28 days
CORRECT ANSWER: C. 10-14 days
Rationale: Normal physiologic weight loss is 5-7%, regained by 10-14 days with
effective feeding. Earlier regaining is unrealistic, and later regaining may indicate
feeding issues requiring assessment.
Question 6: Which of the following is a contraindication to breastfeeding?
A. Maternal HIV in the United States
B. Hepatitis B
C. Mastitis
D. Infant with galactosemia
E. Maternal cannabis use
CORRECT ANSWER: D. Infant with galactosemia
Rationale: Galactosemia requires a lactose-free diet; breast milk contains lactose,
making it contraindicated. HIV is contraindicated in the US, hepatitis B is safe with
vaccine, and mastitis is treated while continuing feeding.
Question 7: The Baby-Friendly Hospital Initiative's Step 4 requires:
, CLC Exam Test Bank 2025/2026 | Certified Lactation Counselor Exam Study
Guide & Practice Questions | CLC Certification Exam Prep | Breastfeeding &
Lactation Physiology, Breast Anatomy, Lactogenesis, Prolactin & Oxytocin,
Milk Production & Milk Ejection, Infant Feeding, Latch & Positioning,
Breastfeeding Assessment, Maternal & Infant Health, Common
Breastfeeding Challenges, Engorgement, Mastitis, Sore Nipples, Low Milk
Supply, Pumping & Milk Storage, Prematurity, Infant Nutrition, Counseling &
Communication, Cultural Competence, Ethics, Public Health & Evidence-
Based Lactation Support | Comprehensive Questions & Detailed Rationales
A. Rooming-in 24 hours a day
B. Initiation of breastfeeding within 1 hour of birth
C. No pacifiers or artificial nipples
D. Exclusive breastfeeding from birth
E. Practice rooming-in, allowing mothers and infants to remain together 24 hours
a day
CORRECT ANSWER: B. Initiation of breastfeeding within 1 hour of birth
Rationale: Step 4 promotes early skin-to-skin contact and feeding initiation within
one hour to establish lactation. Rooming-in is Step 7, no pacifiers is Step 9, and
exclusive breastfeeding is Step 6.
Question 8: Reverse pressure softening is most helpful for:
A. Plugged ducts
B. Severe engorgement with flat nipples
C. Low milk supply
D. Nipple vasospasm
E. Mammary candidiasis
CORRECT ANSWER: B. Severe engorgement with flat nipples
Rationale: Reverse pressure softening reduces edema around the areola, aiding
latch by temporarily softening the tissue. It does not address plugged ducts,
supply issues, vasospasm, or fungal infections.
Question 9: The milk-secreting cells of the alveolus are called:
A. Myoepithelial cells
B. Lactocytes
Guide & Practice Questions | CLC Certification Exam Prep | Breastfeeding &
Lactation Physiology, Breast Anatomy, Lactogenesis, Prolactin & Oxytocin,
Milk Production & Milk Ejection, Infant Feeding, Latch & Positioning,
Breastfeeding Assessment, Maternal & Infant Health, Common
Breastfeeding Challenges, Engorgement, Mastitis, Sore Nipples, Low Milk
Supply, Pumping & Milk Storage, Prematurity, Infant Nutrition, Counseling &
Communication, Cultural Competence, Ethics, Public Health & Evidence-
Based Lactation Support | Comprehensive Questions & Detailed Rationales
Question 1: Which hormone is primarily responsible for the milk ejection (let-
down) reflex?
A. Progesterone
B. Estrogen
C. Prolactin
D. Oxytocin
E. Cortisol
CORRECT ANSWER: D. Oxytocin
Rationale: Oxytocin triggers the milk ejection reflex by causing myoepithelial cells
surrounding the alveoli to contract, expelling milk into the ducts. Prolactin is
responsible for milk synthesis, while progesterone and estrogen inhibit lactation
during pregnancy.
Question 2: A mother reports painful, cracked nipples that began on day 4
postpartum. The most likely cause is:
A. Oversupply
B. Poor latch
C. Thrush
D. Raynaud's phenomenon
E. Mammary dysbiosis
CORRECT ANSWER: B. Poor latch
Rationale: Poor latch causes nipple trauma through improper positioning, leading
to cracking and pain. Oversupply causes engorgement, thrush involves fungal
infection, and Raynaud's phenomenon causes vasospasm with blanching.
,CLC Exam Test Bank 2025/2026 | Certified Lactation Counselor Exam Study
Guide & Practice Questions | CLC Certification Exam Prep | Breastfeeding &
Lactation Physiology, Breast Anatomy, Lactogenesis, Prolactin & Oxytocin,
Milk Production & Milk Ejection, Infant Feeding, Latch & Positioning,
Breastfeeding Assessment, Maternal & Infant Health, Common
Breastfeeding Challenges, Engorgement, Mastitis, Sore Nipples, Low Milk
Supply, Pumping & Milk Storage, Prematurity, Infant Nutrition, Counseling &
Communication, Cultural Competence, Ethics, Public Health & Evidence-
Based Lactation Support | Comprehensive Questions & Detailed Rationales
Question 3: According to the ALPP Code of Ethics, a CLC must:
A. Promote exclusive formula feeding when requested
B. Respect the mother's informed decision even if it differs from evidence-based
recommendations
C. Refuse to counsel mothers who choose not to breastfeed
D. Share client information with employers without consent
E. Prioritize institutional policies over maternal autonomy
CORRECT ANSWER: B. Respect the mother's informed decision even if it differs
from evidence-based recommendations
Rationale: ALPP ethics emphasize client autonomy and non-judgmental support,
providing information for informed choices. Options A, C, D, and E violate ethical
principles by promoting bias, refusal of care, confidentiality breach, or
institutional overreach.
Question 4: The primary source of energy in mature human milk is:
A. Protein
B. Lactose
C. Fat
D. Oligosaccharides
E. Water
CORRECT ANSWER: C. Fat
Rationale: Fat provides approximately 50% of calories in mature milk, supporting
growth and brain development. Lactose provides about 40%, protein about 10%,
and oligosaccharides are prebiotics rather than primary energy sources.
,CLC Exam Test Bank 2025/2026 | Certified Lactation Counselor Exam Study
Guide & Practice Questions | CLC Certification Exam Prep | Breastfeeding &
Lactation Physiology, Breast Anatomy, Lactogenesis, Prolactin & Oxytocin,
Milk Production & Milk Ejection, Infant Feeding, Latch & Positioning,
Breastfeeding Assessment, Maternal & Infant Health, Common
Breastfeeding Challenges, Engorgement, Mastitis, Sore Nipples, Low Milk
Supply, Pumping & Milk Storage, Prematurity, Infant Nutrition, Counseling &
Communication, Cultural Competence, Ethics, Public Health & Evidence-
Based Lactation Support | Comprehensive Questions & Detailed Rationales
Question 5: A term infant born at 39 weeks should regain birth weight by:
A. 3-5 days
B. 7-10 days
C. 10-14 days
D. 21 days
E. 28 days
CORRECT ANSWER: C. 10-14 days
Rationale: Normal physiologic weight loss is 5-7%, regained by 10-14 days with
effective feeding. Earlier regaining is unrealistic, and later regaining may indicate
feeding issues requiring assessment.
Question 6: Which of the following is a contraindication to breastfeeding?
A. Maternal HIV in the United States
B. Hepatitis B
C. Mastitis
D. Infant with galactosemia
E. Maternal cannabis use
CORRECT ANSWER: D. Infant with galactosemia
Rationale: Galactosemia requires a lactose-free diet; breast milk contains lactose,
making it contraindicated. HIV is contraindicated in the US, hepatitis B is safe with
vaccine, and mastitis is treated while continuing feeding.
Question 7: The Baby-Friendly Hospital Initiative's Step 4 requires:
, CLC Exam Test Bank 2025/2026 | Certified Lactation Counselor Exam Study
Guide & Practice Questions | CLC Certification Exam Prep | Breastfeeding &
Lactation Physiology, Breast Anatomy, Lactogenesis, Prolactin & Oxytocin,
Milk Production & Milk Ejection, Infant Feeding, Latch & Positioning,
Breastfeeding Assessment, Maternal & Infant Health, Common
Breastfeeding Challenges, Engorgement, Mastitis, Sore Nipples, Low Milk
Supply, Pumping & Milk Storage, Prematurity, Infant Nutrition, Counseling &
Communication, Cultural Competence, Ethics, Public Health & Evidence-
Based Lactation Support | Comprehensive Questions & Detailed Rationales
A. Rooming-in 24 hours a day
B. Initiation of breastfeeding within 1 hour of birth
C. No pacifiers or artificial nipples
D. Exclusive breastfeeding from birth
E. Practice rooming-in, allowing mothers and infants to remain together 24 hours
a day
CORRECT ANSWER: B. Initiation of breastfeeding within 1 hour of birth
Rationale: Step 4 promotes early skin-to-skin contact and feeding initiation within
one hour to establish lactation. Rooming-in is Step 7, no pacifiers is Step 9, and
exclusive breastfeeding is Step 6.
Question 8: Reverse pressure softening is most helpful for:
A. Plugged ducts
B. Severe engorgement with flat nipples
C. Low milk supply
D. Nipple vasospasm
E. Mammary candidiasis
CORRECT ANSWER: B. Severe engorgement with flat nipples
Rationale: Reverse pressure softening reduces edema around the areola, aiding
latch by temporarily softening the tissue. It does not address plugged ducts,
supply issues, vasospasm, or fungal infections.
Question 9: The milk-secreting cells of the alveolus are called:
A. Myoepithelial cells
B. Lactocytes
