Milk Production & Breast Anatomy (139-146)
Cooper's Ligaments
suspensory ligaments; fibrous bands extending from the inner breast surface to the chest wall muscles. They run vertically, attaching to the deep layer of subcutaneous tissue to the dermis layer of the skin.
Hypoplasia
the incomplete development of an organ or tissue. Tubular shape, may have large aerolas, frequently asymmetrical and widely spaced. Increased risk for insuifficient milk production.
Something is responsible for stimulating another gland
Define Trophic
Breast maturation during puberty. pituitary gonadotropins raise estrogen levels resulting in more ducts, fat, and appearance of lobules.
Describe the main components of the process of Thelarche
Mammogenesis at 4-5 Weeks
Development begins. Milk lines develop (aka galactic streak/mammary ridge)
Lactogenesis 1 process
Differentiation occurs of alveolar epithelial cells into lactocytes that secrete colostrum. Lactose, total proteins, and immunoglobulin increase. Sodium and chloride decrease. Nutrients from bloodstream go towards preparing to breastfeed.
Montgomery glands
Milk and sebaceous oil glands present on the aerola. They contribute to breastfeeding, early grwoth and lactogenesis. Helps newborns find the breast and creates lubrication.
Milk Expulsion Process
Oxytocin commands myoepithelial cells to begin contracting and pushing milk out of the alveoli into the ducts, onto the nipple. The more oxytocin is released, the more the hypothalamus is told to increase prolactin and oxytocin production.
Stroma
Supporting tissue of the breast including the connective tissue, fat tissue, blood vessels, nerves and lymphatics
True
T or F: Breast size can decrease between 6-9 months postpartum
False
T or F: Breast size has an impact on milk production capacity.
Adipose tissue
Fat surrounding the glandular tissue to provide protection and warmth to the mammary structures
True
T or F: Exclusive breastfeeding mothers have a higher level of oxytocin than those that mix feed
Lactogenesis 1 definition
First stage of lactation beginning around mid-pregnancy until day 2ish postpartum. Driven by hormones and radically changing the appearance of the aerola/breast.
False
T or F: First time moms usually have high protractility of full extension to junction of the newborn's hard/soft palate
False
T or F: Nipple types plays a part in the ease and effectiveness of breastfeeding
True
T or F: Oxytocin levels rise and fall within the minutes starting and ending a feed, with suckling and skin to skin
False
T or F: Prolactin levels are lower during the day than at night
True
T or F: What matters in effectiveness in breastfeeding is how flexible the aerola and nipple tissue is and how much a deep latch can be attained.
True
T or F: Women with more montgomery glands have babies with more weight gain than those with fewer
Hypertrophy
Abnormally large breast (gigantomastia)
Hypomastia
Abnormally small breast
Flat nipple
Absence of the nipple shaft that may be soft and pliable. Can be able to form ridge to allow for baby to latch. May remain unchanged when stimulated, or even retract when compressed.
Left and right refers to mother's point of view. Upper & lower outer and inner quadrants
Breast Quadrants
Lactogenesis 4
Breast returns to non-productive state and breast milk sodium levels increase.
Nipple Aerola Complex (NAC)
A round structure cromprised of muscle fibers on the breast, about 3-6 cm long and usually positioned about 4th rib level.
Nipple (Mammary pipilla)
At the center of the aerola, on average 10-12 mm and height of 9-10 mm. Lined with 10-20 pores leading to interior lactation anatomy providing a path to secrete out of the breast.
FIL- Feedback Inhibitor of Lactation
Autocrin mechanism of lactation not fully understood yet. When breasts stay full, FIL isn't removed, reducing milk production.
17-33 ml/hr
Average rate of milk production
Lobes
Clusters of lubules filled with alveoli.
Amastia
Congenital absence of the breast tissue and the nipple. One breast gone points to Poland's syndrome.
10-100
Each breast contains how many alveoli?
15-25
Each breast contains how many lobes?
Tail of Spence
Extension of the mammary tissue into the armpit, which may become full of milk and engorge for some women
Polymastia
Extra breast tissue
Hyperthelia
Extra nipple without any accompanying mammary tissue
Polythelia
Extra nipples with mammary tissue
Estrogen
Growth hormone that causes ductal system proliferation nd differentiation and the growth of connective tissue between the ducts. Produced by the ovaries, adrenals, and fat tissue.
Oxytocin
Hormone responsible for muscle contraction of alveoli. Produced in the posterior pituitary.
Prolactin
Hormone responsible for nipple and areolar growth, stimulates mammary secretory epithelial cells to produce milk. Produced in the anterior pituitary. Essential for initiation and maintenance in milk production.
Oxytocin release
Hormone responsible for the milk ejection reflex by contracting the myoepithelial cells around the alveoli
Progesterone
Hormone that increases the size of the lobes, lobules and alveoli. Produced by the ovaries, placenta and adrenal glands.
Progesterone
Hormone that stimulates the growth of alveoli
Both hormones are together only for a short time after birth. They promote bonding and nesting and the 5 senses increase production.
How do estrogen and oxytocin work together?
Rise directly following birth, then rise/fall shortly thereafter based on frequency and intensity of nipple stim
How do prolactin levels differ during pregnancy and postpartum?
May increase with breastfeeding and additional lactation experiences. More stretching and more movement = more increasing of comfort over time.
How does protractility change over time?
A week
How long does it take prolactin to return to non-pregnant levels if a woman doesn't breastfeed?
Breast Type 3
Hypoplasia of the lower medial and lateral quadrants
Breast Type 2
Hypoplasia of the lower medial quadrants
Relief for engorgment of the tail of spence
Ice packs and green cabbage
Serotonin (a neurotransmitter) believed to help regulate mood, appetite, digestion, sleep, memory, sexual desire and function
In theory, what is FIL really hypothesized to be?
Higher concentration and less milk production
Less stimulation and milk removal leads to higher or lower PIF concentration? and higher or lower milk production?
Lactogenesis 3 definition
Maintenance of milk production from day 9 on. Also known as galactopoiesis.
Pseudo-inverted or dimpled nipple
May appear inverted, but everts with compression or stimulation
Lactocytes
Milk making cells lining the interior of each alveolus
Milk Ejection/Letdown reflex
Milk releasing from the breast in response to stimulation. Nipple stimulation releases prolactin and oxytocin, and the process becomes conditioned over time- meaning just thinking about the baby will initiate it
Lower concentration and higher milk production
More stimulation and milk removal leads to what concentration of PIF and level of milk production?
Retracted Nipple
Most common type of nipple inversion. Appears everted, but retracts with stimulation.
Myoepithelial cells
Muscle fibers that surround the outside of the alveoli, aiding in milk contraction
Amazia
Nipple and aerola without breast tissue
Mammogenesis at 12-16 Weeks
Nipple and areola formation. Epithelial cells develop into buds and epithelial branches form
Highly vascularized secretory cells extract water, amino acids, fats, vitamins and minerals and other substances from blood
On a chemical level, how is milk made?
Hyperplasia
Overdevelopment of breast
Lactiferous ductules
Passageways for the milk formed in a branched network much like branches of a tree. Milk is moved from the alveoli into ductules joining into the ducts towards the nipple.
Mammogenesis at puberty
Primary & secondary duct growth continues with each menstrual cycle.. Estrogen, steroids and growth hormones affect the ducts.
Establishes milk synthesis
Prolactin does what in lactogenesis 3?
200-400 ng/ml
Prolactin levels rise during pregnancy from 10-20 ng/ml to what at term?
Prolactin receptor theory
Prolactin receptors in the basement membrane of alveoli where lactocytes are attached. Milk accumulates and the shape of the lactocyte is distorted. Prolactin can't bind to the receptor, down-regulating the rate of milk production.
TSH (Thyroid stimulating hormone)
Promotes mammary growth and lactation. Hypothyroidism can contribute to low milk production.
Common Nipple
Protrudes at rest and becomes erect with stimulation
Lymphatics
Referring to most drainage in the breast, including immunity bearers and primary axillary
Breast Type 1
Round tissue and fullness of all quadrants
Breast Type 4
Severe hypoplasia, minimal breast tissue
Mammogenesis at 15-25 Weeks
Shallow epithelial depressions. Mammary pits begin to form, if not, inverted nipples result
Visual signs of lactogenesis 1
Skin appears thinner, veins more prominent, diameter of areola increases, nipples more erect, color of aerola darkens, montgomery glands enlarge.
Prolactin-inhibiting factor (PIF)
Stimulates dopamine release which inhibits prolactin release. Nipple stimulation and milk removal suppresses PIF, as well as other medications.
Cortisol
Stress hormone that may delay lactogenesis 2 if extremely present in high amounts
Lumen
The hollow storage space for milk inside of the alveolus once created.
60%
The internal mammary artery supplies how much blood to the breast?
30%
The lateral thoracic artery provides 30% of blood to the breast?
The more milk is made!
The more milk that leaves the breast...
Lactogenesis 2 process
The onset of copious milk secretion, then it begins to level off. First, engorgement occurs as supply arrives. There's a decrease in sodium, chloride and protein in milk due to closure of gaps between cells. Milk increases in lactose and milk lipids.
Lactogenesis
The process of lactation!
Lactogenesis 2 definition
The secretory activation process in lactation beginning approximately day 2 to day 8 postpartum
Alveoli
Tiny sacs of the mature mammary gland lined with lactocytes (epithelial cells). Where milk production occurs. They consist of epithelial cells encased in a dense network of myoepithelial cells.
Inverted Nipple
True inversion of the nipple at rest and with stimulation. Adhesions may be present on the skin folds.
Poland syndrome
Unilateral breast hypoplasia with hypoplasia of the thorax and pectoral muscles
Placenta removal
What causes the rapid drop of progesterone, triggering lactogenesis stage 2?
Suppress milk production
What do high levels of estrogen do?
Causes milk ejection, reduces stress, causes uterine contractions, establishes caring and bonding behaviors
What does oxytocin do in lactogenesis 3?
Illness, chemo, radiation, injury or surgery to the chest
What effects breast development and may cause anomolies?
Prolactin
What hormone can delay ovulation?
Progesterone during pregnancy
What hormone inhibits lactation during pregnancy since it interferes with prolactin at the receptor level?
Oxytocin
What hormone spikes to contract the uterus, controlling postpartum bleeding and helping uterine ivolution?
Estrogen, progesterone, adrenals, and pituitaries
What hormones control the cell division process during puberty and thelarche?
Growth of ducts and lobuloalveolar (ducts and segments) systems in the breast
What is responsible for the growth of the breasts during pregnancy?
Endocrine to autocrine supply
What kind of supply switch happens in lactogenesis 2?
16-20 weeks gestation, even if the pregnancy terminates
When is colostrum first produced during pregnancy?
4th Nerve
Which nerve supplies the largest amount of sensation to the nipple and aerola?
ACTH (adrenocorticotropic hormone)
Works with prolactin and progesterone to promote mammary growth