Breastfeeding Flashcards
Current Recommendations for Infant Feeding
- Exclusive breastfeeding for first 6 months of life
- Breast feeding can continue for 2+ years
- iron-fortified is the only alternative to breastmilk for the first 6 months
- solids can be introduced after 6 months
optimal method of feeding infants
breastfeeding
What is exclusive breastfeeding?
Only breastmilk
* Includes: Breastmilk fed from the breast and expressed breastmilk with inclusion of supplements and medicine
* not including: water, formula other liquids or solids
Benefits of breastfeeding for the Infant
- contains all the nutrients the infant needs in the ideal proportions
- helps development of the intestinal tract and immune system
- lower risk of infections, allergies, SIDS
- associated with enhanced cognitive development and lower risk of obesity
Benefits of breastfeeding for the mother
- economical and generally convenient
- promotes weight loss
- psychological benefits from the physical contact
- delayed return of fertility
- associated with lower risk of breast and ovarian cancer
Lactation
- the production of milk
- the period following childbirth when milk is formed in the breasts
breasfeeding
the process of nourishing an infant at the breast
What is the main organ of lactation and breastfeeding?
Mammary glands
* alveolus is active machinary
* contractile unit to get milk out
Where do lactation materials come from?
“Raw materials” supplied by maternal circulation (maternal stores, diet) and may be transported in and out of aveolar gland cells or “processed” in the gland cells and then final product secreted into ducts in centre of cluster of alveoli
What are the stages of lactation?
- Stage I: Starts in late pregnancy; prep action
- Stage II: 3-10 days post-partum
- Stage III: ~10 days post-partum
Key hormone of lactation
Prolactin
* levels rise from early pregnancy and develop secretory portions of gland
What occurs in stage I lactation?
- increased lactose, protein, immunoglobulin in gland in third trimester
- first fluid after delivery: colostrum (1-3 days)
What occurs in stage II lactation?
3-10 days post-partum
* secretory activation and transitional milk
* increased blood flow and glucose uptake –
“milk comes in” reflecting supply and demand
What occurs in stsge III lactation?
~10 days post-partum
* mature milk
Initiation of the FIRST lactation
At delivery of placenta, abrupt ↓ in human placental lactogen, estrogen and progesterone
* removal of estrogen and progsterone are triggers for milk secretion
What hormones maintain lactation?
- Prolactin (anterior pituitary)
- Oxytocin (posterior pituitary)
Role of prolaction
stimulates milk production
* levels high in first weeks, gradually decline but rise with sucking
Role of oxytocin
release of milk
* stimulated by sucking, sound of baby crying, sex etc.
* triggers contraction of myoepithelial cells to permit milk ejection = let-down reflex
What is important about environment for oxytocin?
mother breastfeeding needs to be in a relaxed environment as stress can reduce stimulus
How much breastmilk is produced?
Production related to demand
* Increased production in feeding multiples
* Production is not dependent on breast size
Basic principles of breastfeeding
- started during the alert period immediately after delivery
- feeding “on demand” rather than by schedule so typical newborns will feed 8-12 per 24 hrs
- offering 1st breast until finished, then 2nd breast; next feeding offer the second breast first
Early infant cues of hunger
hands to mouth, head movement
* crying is not an early cue
Key to optimal breastfeeding?
Correct positioning of baby and correct latching
* allows baby to get milk and should not be painful
What is “the art” of sucking?
When “letdown” induced, sucking becomes slow, rhythmic
* suck-swallow-breathe pattern
How long should active feeding be and what is the satiety cue?
- Active feeding 5-20 min (maximum ~30 min)
- satiety cue: baby releases breast spontaneously
What is a later cue of hunger?
crying
What are the types of breastmilk?
- colostrum
- transtional milk
- mature milk
What is the first breastmilk?
Colostrum (day 1-3)
* yellow color due to beta-carotene
* low volume (2-10 ml/feed)
* lower energy
* higher protein (IgA, lactoferrin) and growth factors
* adequate to meet infant needs in first few days
What nutrients might vary in breastmilk composition?
- macronutrients: not the amount of fat but the types of fat are what will change
- water soluble: B vitamins; thiamin; riboflavin; niacin; B6; B12; choline; vitamin C
- fat soluble: vitamin A; vitamin D
- minerals: iodine
What components of breastmilk do not depend on maternal diet?
- macronutrients: CHO (uptake always maximal), proteins
- water soluble: folate
- fat solbule: vitamin E
- mineral: all except iodine
mature breastmilk compostion
Mature milk composition varies
* night/morning vs afternoon/evening
* early in feed vs later in feed
How does night/morning vs afternoon/evening vary mature breastmilk?
night/morning is lower in fat
How does early in feed vs later in feed vary in mature milk?
foremilk (early in feed) higher in lactose and lower in fat than hindmilk (later in feed)
* hence critical for baby to feed on one side completely so they get both foremilk and hind milk
What is the average nutrient composition of mature milk?
energy content: 0.67 kcal/g
* 55% lipid
* 38% lactose
* 7 % protein (very bioavailable)
How much mature breastmilk is produced?
700-900 g produced each day
* less if partially breastfeeding such as starting to eat solids
What is the CHO in breastmilk?
Virtually 100% the disaccharide lactose: glucose and lactose
* also contains some oligosaccharides
What are the oligosaccharides important for?
May prevent pathogenic organisms from binding to gut and promotes growth of ‘good’ bacteria (prebiotic)
* microbiome development and infection prevention
What is the PRO in breastmilk?
- Most abundant: casein, α-lactalbumin, lactoferrin, sIgA, lysozyme, serum albumin
- 20% of nitrogen non-protein: including urea, free amino acids, nucleotides
How much protein is in breastmilk?
- 10 g protein/L breastmilk
How is breastmilk different from cows milk?
Qualitatively different from cow milk
* Human milk: 70% whey, 30% casein
* Cow milk: 20% whey, 80% casein
What is the benefit of higher whey content in breastmilk?
- Easier to digest
- More rapidly digested/ emptied from stomach
- Soluble in acid
- High in leucine and can be directly anabolic to muscle through mTOR pathway
Content of lipids in breastmilk
50% calories from lipid, easily absorbed
* mostly long chain
* medium chain synthesized in gland cells
What are lipids contained in?
Lipid contained in milk-fat globule which is a protein carrier for triglycerides
What changes occur in breastmilk lipids with maternal diet?
Quality changes but not quantity
* dietary influence of AA and DHA
* if mother is losing weight – fatty acids from adipose tissue could be incorporated into milk so SFA and MUFA
Content of vitD in breastmilk
~22 IU/L, fairly constant throughout pregnancy
* likely inadequate to meet needs, especially: darker skin, protection from sun, northern latitudes
* supplement is recommended for infants
Content of vitK in breastmilk
low in breast milk so inadequate synthesis
* all infants receive Vitamin K at birth until they can make their own through developed microbiome
Supplements recommended for breastfed infants from Health Canada
- Vitamin K: 1 mg IM at birth
- Vitamin D: 400 IU/d birth to 12 months
What is not recommened to give infants?
- water
- other milk
- multivitamin
- supplements besides vitK and vitD
What other supplement might preterm infants need?
often require an iron supplement since most iron deposition happens in the last trimester and need it to last them 6 months
Calcium and phosphorous content of breastmilk
lower than cows milk but highly bioavailable
* calcium bound to casein
* lactose enhances calcium absorption
* stable throughout lactation
Iron content of breaskmilk
low in breastmilk and content ↓ throughout lactation but it is very bioavailable as lactoferrin
* lactoferrin also sequester iron away from microbes so protective
* does not meet infant requirement past 6 months
Zinc content of breastmilk
concentration higher than mother’s plasma so ative transport occurs
* protein bound, increases bioailabilty
* need for all things realted to growth
Choline content of breastmilk
increased need during lactation
* amount in breastmilk reflect maternal intake
* APrON cohort data showed only 10% met the AI for choline
* high demand from fetus and depletes mom so need to be cognizent of status
What is choline important for?
important methyl donor for growth
* brain development, lipid digestion/absorption/transport, intestinal health
Current daily recommendations for choline
Requirements increase during periods of rapid growth and development
* AI women: 425 mg/d
* AI pregnancy: 450 mg/d
* AI lactation: 550 mg/d (same for men)
What is a good source of choline?
eggs
non-nutritive components of breastmilk
- immune
- growth factors
- other
what are immune components of breastmilk?
- Secretory IgA
- Lactoferrin
- Lactadherin
- Lysozyme
- Lymphocytes
- Cytokines
- Oligosaccharides
Role of Secretory IgA
line mucosal surfaces, prevent microbial attachment
* forms layer between microbe and host
Role of lactoferrin
antimicrobial activity
role of lactadherin
prevents rotaviral infection
* adhesion and entrance of a virus
role of lysozyme
cleaves bacterial cell walls
* directly destroys bacteria
Role of Lymphocytes
cytokine production
Role of Cytokines
protection, inflammation
Role of Oligosaccharides
prebiotic (eg bifidus factor)
What are the growth factor components of breastmilk?
- Epidermal Growth Factor (EGF)
- Neuronal growth factors
- Insulin-like growth factor (IGF) and binding protein
- vascular endothelial growth factor
- erythropoietin
- calcitonin
Role of Epidermal Growth Factor (EGF)
maturation and healing of the intestinal mucosa
Role of Neuronal growth factors
maturation of enteral nervous system (motility)
Role of Insulin-like growth factor (IGF) and binding protein
regulation of tissue growth
Role of vascular endothelial growth factor
stimulate blood supply
Where are the non-nutritive components produced/ secreted?
- Produced and secreted by the mammary gland cells
- Produced by cells carried within the milk
- Passed from maternal serum through the
gland cell
Present in the milk fat globule (MFG)
What is significant about the bioactive components of breastmilk?
Contains variety of factors that have profound role on infant survival and growth; not merely nutrition
* property of breastmilk that is not replicated in breastmilk replacements (formulas)
* breastmilk as a functional food
What are other bioactive components of breastmilk?
Leptin, adiponectin, ghrelin and obestatin present in breastmilk
* involved in regulation of metabolism and/or appetite
* possible link between breastfeeding and lower risk of obesity
* Influence on appetitive, energy metabolism, talk to muscle, bones, adipocytes
enery recommendations for breastfeeding women
TEE non-pregnant women + energy costs of milk production (volume x energy density) – energy mobilization from tissue stores (stored up energy over pregnancy)
* 0-6 months = non-pregnant EER + 500 -170 (extra 330 kcal/d)
* 7-12 months = non-pregnant EER + 400 – 0 (extra 400 kcal/d)
Macronutrient recommendations for breastfeeding women
- CHO RDA: 210 g/d
- PRO RDA: 1.3 g/kg/d
- LA AIs: 13 g/d
- ALA AIs: 1.3 g/d (200mg DHA/d)
Recommended intake of water
Breastmilk is 88% water
* Non-pregnant women: 2.7L/d
* Pregnancy: 3.0L/d
* Lactating: 3.8L/d
micronutrient reccomendations same as non-pregnant women
- Vitamin D RDA 600IU
- Calcium RDA: 1000mg
- vitamin K, fluoride, magnesium, phosphorus, sodium, chloride
micronutrient recommendations same as pregnancy
thiamin, molybdenum
micronutrient recommendations higher than pregnancy
- Vitamin A RDA 1300ug RAE
- riboflavin, B6, B12, pantothenic acid, biotin, choline, C, E, chromium, copper, iodine, manganese, selenium, zinc, potassium
Why is vitamin A higher during lactation
critical for immune system so RDA is higher
* teratogen in pregnancy though
micronutrient recommendations lower than pregnancy
- Folate RDA 500ug (higher than non-pregnant)
- Iron RDA 9mg (lower than non-pregnant)
- niacin (higher than non-pregnant)
Current recommnedations for diet from Health Canada for breastfeeding women
Follow Eating Well with Canada’s Food Guide
* Nutrient dense diet
* Extra 2-3 servings per day
* Multivitamin with 0.4 mg of folic acid – all women of childbearing age
storing pumped breatmilk under regular collection?
- Room temperature: 3 to 4 hours
- Refrigerator (4C): up to 72 hours
- Refrigerator freezer (-4C): up to 6 months
Storing pumped breastmilk under clean conditions?
properly washed hands, cleaned pump parts
* Room temperature: 6 to 8 hours
* Refrigerator: 5 to 8 days
Breastfeeding rates in Alberta
2019/2020
* 91% initiate breastfeeding
* 29% exclusive breastfeeding until 6 months (do good at start than drop off usually due to difficulty with establishing breastfeeding in the early stages)
Women who breastfeed for 6+ months are more likely:
- married, or some sort of support
- At home, more time off
- Have support networking including a partner that supports breastfeeding
- Older
- Higher income
- To have had a previous positive breastfeeding experience, either themselves or heard from someone else
contraindications to no breastfeeding
- maternal HIV infection
- maternal drugs of abuse
- infant galactosemia
- infant congenital lactase deficiency
contraindications to interruption of breasfeeding
Lactation should be maintained and resumed when safe
* maternal herpes lesions on both breasts
* maternal active TB
* maternal use of some medications e.g. chemotherapy, radioactive isotopes
What are not contraindications to breastfeeding?
- most infections
- most OTC and prescription drugs
- smoking and non-abusive alcohol intake (although should be avoid or limited) usually metabolized in circulation before reach milk
- high level of physical activity
- environmental contaminants
- small breast size or silicone implants
Barriers to breastfeeding
- time/ going back to
- bad experience
- Lack of support or confidence
- Perception of inadequate milk production or adverse infant response to breasmilk (may be generationally driven)
- Discomfort (should not be painful)
- infections
- Other demands
SEM for promoting breastfeeding
What is important at the community level for breastfeeding support?
Health professionals should encourage exclusive breastfeeding for at least 6 months
* breastfeeding counseling before, during and after pregnancy
* health care facility practices: BFHI
* community-based programs and support
Adequacy of breastmilk supply
Supply meets demand
* takes time to establish demand-supply balance
* first few days very little colostrum per feeding (2-10ml)
* normal for baby to lose some weight
* sucking will stimulate milk production
How to know if there’s enough milk - short term
- weight gain after initial weight loss
- ~3 yellow seedy BM/d
- urine clear, light colored, 6 x/day
- baby settled and comfortable for 2-3 hours after feed
How to know if there’s enough milk - long term
growth and developmental milestones
What might cause a failure to thrive?
growth is less then expected due to inadequate intake or digestion, excessive losses, requirements above predicted.
How might failure to thrive be assessed?
Multiple definitions including:
* <5th percentile weight for age, weight for length <50th percentile
* crossing percentile lines downward
Breastfeeding issues/ concerns and how they might be fixed
Common infant gastrointestinal concerns that do not require change in feeding
- colic
- Infrequent bowel movements
- Reflux
- Acute gastroenteritis
Colic
irritability, fussiness, crying
* usually resolves by 4 months; etiology unknown (immature GI motility?)
* small percentage with severe colic respond to maternal dietary cow protein restriction
Infrequent bowel movements
constipation rare in BF infants, normal for BF infants to have bowel movements every 3-4 days
Reflux
common in infants and usually with regurgitation
* Usually goes away
Acute gastroenteritis
- diarrhea secondary to viral infections
- oral rehydration therapy for mild to moderate, iv rehydration for severe with
- continued BF
