Lactation

Question 1

Prolactin (5 things)

Answer 1

Released from the anterior pituitary gland
Prolactin is produced in pregnancy, but milk production is suppressed by oestrogen and progesterone (placental hormones)
Once the placenta is birthed, oestrogen and progesterone drop so prolactin activates milk production in the acini cells
Levels are higher at night
Prolactin is also released when the baby suckles

Question 2

Milk production reflex (7 things)

Answer 2

Baby suckles
Sensory impulses pass from the nipple to the brain
Prolactin is secreted by anterior pituitary gland, goes via blood stream to the breasts
Acini (milk secreting) cells produce milk in time for the next feed
More secreted at night
Suppresses ovulation
Level peaks after the feed, to produce milk for the next feed

Question 3

Oxytocin (5 things)

Answer 3

Works on muscle (myo-epithelial) cells to expel milk
Pulsation action (released in pulses)
Induces feeling of love and well-being
Levels are higher when baby is near
Can be temporarily inhibited by stress

Question 4

Milk ejection reflex

Answer 4

Baby suckles
Sensory impulses from the nipple to the brain
Oxytocin secreted by posterior pituitary gland goes via bloodstream to the breasts
Myo-epithelial (muscle) cells surrounding the alveoli contract
Milk is forced into the lactiferous ducts
Helped by sight sound and smell of baby
Becomes conditioned over time
Hindered by anxiety, stress, pain, doubt
Works before or during the feed to make the milk flow

Question 5

Fil mechanism

Answer 5

Frequent milk removal ensures ongoing milk production
FIL secreted in milk
Build up of FIL blocks further milk production
Removing FIL allows milk production

Question 6

Prolactin receptor theory

Answer 6

Surges of prolactin prime the receptor sites
Expulsion of placenta opens receptor sites
Unprimed receptor sites shut down, reducing potential for milk production
Skin contact and lots of feeds in early days increase potential for long-term milk production

Question 7

Endogenous oxytocin

Answer 7

(Natural)
Crosses the blood-brain barrier
Evokes feelings of love and protectiveness
Stimulated by nurture and touch

Question 8

Synthetic oxytocin

Answer 8

Does not cross the blood brain barrier so does not evoke the same feelings of love and protectiveness