IBCLC cheat sheet

Mammary glands arise from ectodermal mammary ridges (milk lines) at about 6 weeks' gestation.

Fetal mammary development proceeds similarly in both sexes until puberty, when gonadal hormones drive sex-specific growth.

Estrogen promotes ductal elongation; progesterone and prolactin support lobuloalveolar development during puberty and pregnancy.

Lactogenesis I (secretory differentiation) begins mid-pregnancy and produces colostrum.

Lactogenesis II (copious milk secretion) occurs 24–72 hours postpartum after progesterone withdrawal.

Lactogenesis III (galactopoiesis) is maintained by autocrine milk removal rather than endocrine control.

Term newborn gastric capacity is about 5–7 mL on day 1, 20–30 mL by day 3, and 45–60 mL by day 7.

Infant oral structures-fat pads, tongue, hard and soft palate-support sealing and vacuum during suckling.

Prolactin is secreted by anterior pituitary lactotrophs; dopamine tonically inhibits its release, and suckling reduces dopamine.

Oxytocin is released from the posterior pituitary and causes myoepithelial contraction, producing milk ejection.

Milk ejection can be conditioned by infant cry or ritual and is inhibited by pain, stress, or cold.

Progesterone withdrawal after placental delivery is the endocrine trigger for lactogenesis II.

Feedback inhibitor of lactation (FIL) is a milk protein that locally suppresses synthesis when milk stasis occurs.

Milk synthesis is rate-limited by removal frequency and completeness; more frequent emptying increases output.

Fat content of human milk rises within a feed and varies diurnally; foremilk and hindmilk are not discrete.

Prolactin levels are higher at night, supporting nocturnal milk synthesis.

Lactational amenorrhea method requires amenorrhea, exclusive breastfeeding, and infant under 6 months.

Mastitis presents with focal pain, redness, and fever; Staphylococcus aureus is a common pathogen; milk removal continues.

Breast abscess is a fluctuant collection requiring drainage; breastfeeding usually continues on the unaffected side.

Candida infection causes shiny, burning nipples and infant oral thrush; both parent and infant are treated.

Ankyloglossia is diagnosed by functional restriction of tongue mobility, not by frenulum appearance alone.

Neonatal hypoglycemia risk rises with prematurity, small or large for gestational age, and maternal diabetes; early feeding and glucose monitoring apply.

Breastfeeding jaundice reflects insufficient intake; breast milk jaundice occurs later and is usually benign.

Galactosemia contraindicates breast milk; phenylketonuria may allow partial breastfeeding with monitoring.

Insufficient glandular tissue, PCOS, retained placenta, and Sheehan syndrome can reduce milk production.

Relative infant dose (RID) = infant dose (mg/kg/day) ÷ maternal dose (mg/kg/day); RID under 10% is generally low risk.

Drug transfer into milk is lower with high maternal protein binding, high molecular weight, and poor lipid solubility.

Infant factors-gestational age, hepatic and renal clearance-modify risk more than milk-to-plasma ratio alone.

Codeine is avoided in breastfeeding because CYP2D6 ultrarapid metabolizers produce unsafe morphine levels.

Acetaminophen, ibuprofen, most penicillins, insulin, heparin, and vaccines are generally compatible with breastfeeding.

Radioactive iodine-131 and cytotoxic chemotherapy are contraindications during breastfeeding.

Alcohol enters milk at plasma concentration; waiting about 2 hours per standard drink reduces infant exposure.

Caffeine up to about 300 mg/day is generally acceptable; infant irritability may occur.

Domperidone and metoclopramide are galactagogues with limited evidence; domperidone carries QT-prolongation risk.

Breastfeeding self-efficacy is a modifiable predictor of initiation, exclusivity, and duration.

Skin-to-skin contact after birth supports breastfeeding initiation and reduces infant stress.

Postpartum depression and anxiety are associated with earlier breastfeeding cessation; EPDS is a validated screen.

Responsive feeding follows infant cues rather than a fixed schedule.

Rooming-in increases breastfeeding frequency and duration.

Partner and family support are consistently associated with longer breastfeeding.

Breastfeeding grief after unmet goals can mimic loss; validation and referral support adjustment.

Attachment theory links sensitive, contingent caregiving with secure infant attachment.

The WHO International Code (1981) restricts marketing of breast-milk substitutes, feeding bottles, and teats.

The Baby-Friendly Hospital Initiative's Ten Steps improve breastfeeding initiation and exclusivity.

Breastfeeding rates vary by income, race, education, and geography; disparities persist in high-income countries.

Paid maternity leave length is positively associated with breastfeeding duration.

Workplace lactation accommodation-breaks and private space-increases duration and exclusivity.

WIC provides breastfeeding support and food packages to low-income US families.

Peer counselor programs improve exclusivity among low-income and minority populations.

Cultural norms and media portrayals shape infant feeding decisions.

Culture shapes infant feeding beliefs, roles, and rituals; cultural humility avoids applying one norm universally.

Explanatory models elicit a family's own understanding of health and feeding.

Andragogy emphasizes relevance, problem-centered learning, and learner experience.

Teach-back asks learners to restate or demonstrate information to confirm understanding.

Health literacy strategies include plain language, chunking, and limiting numeric detail.

Motivational interviewing uses open questions, affirmations, reflections, and summaries (OARS).

Shared decision-making combines clinician evidence with family values and preferences.

Evidence does not support matching teaching to learner 'styles'; multimodal teaching is preferred.

Asymmetric latch: chin contacts breast first, nose is clear, gape is wide, and more areola shows above than below.

Cradle, cross-cradle, football, and side-lying holds alter maternal hand support but not infant oral mechanics.

Hand expression uses a C-hold behind the areola with pressure toward the chest, not pinching.

Correct pump flange size lets the nipple move freely without rubbing; common sizes are 21–27 mm.

Reverse pressure softening moves edema away from the nipple base to permit a deeper latch.

Paced bottle feeding uses an upright position, slow-flow nipple, and pauses to follow infant cues.

A supplemental nursing system delivers supplement at the breast while stimulating milk production.

Cup feeding avoids artificial nipples and uses controlled tipping and pauses.

Test weighing before and after a feed estimates milk intake on a sensitive scale.

LATCH scores latch, audible swallowing, nipple type, comfort, and hold on a 0–10 scale.

Newborn weight loss up to 7–10% by days 3–5 is common; greater loss warrants feeding assessment.

Most newborns regain birth weight by about 2 weeks; failure warrants evaluation.

Diaper counts: meconium by day 1, transitional stools by days 2–4, and 6+ wet diapers by days 5–6.

Oral exam assesses tongue mobility, palate integrity, and suck function.

Jaundice is assessed by bilirubin measurement; transcutaneous screening is followed by serum confirmation when indicated.

History includes pregnancy, birth, medications, feeding frequency, output, and weight trajectory.

Referral is indicated for structural, neurologic, or metabolic concerns beyond lactation scope.