Lactation Flashcards
lactation - general
- Following birth
- Provides milk of appropriate composition and quantity to fully sustain the growth and development of the young until weaning
- Breast changes are often the first subjective indication of conception
- Breast development during pregnancy = Secretory Differentiation
o Milk production after birth = Secretory Activation
secretory differentiation
- Breast growth during pregnancy occurs through terminal end buds
o Increasing Prolactin and Lactose levels during pregnancy linked to breast development - lactose secreted in the urine
o Terminal
pregnancy hormones that lead to breast growth
'lactogenic hormone complex' o oestrogen o progesterone o growth hormone o epidermal growth factor o fibroblast growth factor o insulin-like growth factor o parathyroid hormone related protein o human placental lactogen (hPL)
secretory activation
- Onset of copious milk secretion
- Day 1- 3 days - colostrum
o 7 - 123 mL per day
o Rich in protein - immunoglobulins, lysozyme and lactoferrin - Day 3 - 6 -> mature milk
o 400 - 900mL per day
o Change in milk composition
o inc lactose, inc water, inc protein - Following birth delivery of the placenta => dramatic fall in progesterone => Secretory Activation
- Progesterone withdrawal initiates Secretory Activation.
- Increase in Lactose associated with milk production.
- Initiation of copious milk secretion
hormones required for lactation
Permissive o Prolactin o Insulin o Adrenal Cortisol Trigger o Removal of progesterone Milk Ejection o Oxytocin Lactose synthesis determines milk volume (osmotic)
delayed secretory activation
May be caused by:
- Premature delivery
- Type1 Diabetes
- Obesity
- Prolactin insufficiency
- Delayed progesterone withdrawal (**retained placental fragments)
- Hormone therapy
- Anaesthetic agents (caesarean)
milk ejection reflex (MER)
stimuli can be conditioned and can be inhibited by stress - invasive procedures can reduce MER
stimulus: Sensory nerves, spinothalamic tract –> brain stem –> brain stem –> hypothalamus –> post pituitary –> oxytocin release –> maternal circulation –> receptor binding –> myoepithelial cell contraction –> milk ejection
autocrine control of milk synthesis
supply vs demand (appetite) and inhibition
local control of milk synthesis
short term: hours
medium term: days - weeks
long term: weeks - months
frequency of breastfeeding, in part, explain many problems such as
mastitis sore nipples reflux colic unsettled baby low supply over supply
brestmilk as a functional food - milk composition
contains nutrients and substances that confers health benefits
- lactose, protein, fat
benefits of breastfeeding for mother
- Recovery from childbirth
- Body weight loss
- Suppression of maternal fertility
- Bone mineralization
- Cholesterol clearance
- Diabetics – glucose control
- Decreased risk of breast & ovarian cancer
- Self esteem
benefits of breastfeeding for baby
- ‘Gold Standard’ Infant Food
- Ideal nutrition
- Species specific
- Facilitates Growth & Development
- Increased IQ
- Better eyesight
- Protect against illness
protein, fats, CHO, vitamins and minerals adapted to the infants digestive capacity and metabolic requirements
non-nutritional components of breastmilk
- Antimicrobial factors
- Growth factors
- Cytokines and anti-inflammatory factors
- Digestive enzymes
- Hormones
Complement Infant’s Immature Metabolic Capacity
- Digestive, Hepatic, Renal, Visual, Skeleton, Endocrine,
- Vascular, Immune, Central Nervous System
benefits for the immature digestive system
Breastmilk contains:
- Digestive Enzymes
- Glutamate/Glutamine (as free amino acids)
- Oligosaccharides
- Influences normal gut flora
- Enzymes promote gut maturation and gut repair
- Enzymes increase bio-availability of trace elements
- Promotes intestinal growth
o Taurine, ethanolamine, interferon
