Anatomy and physio of lactation Flashcards
name 4 computes of the breasts
Glandular tissue
Connective tissue
Lymph
Adipose (fatty) tissue
what is the function of glandular tissue in the breast
makes and transports the milk
Blood supply which nourishes the breast tissue and provides the nutrients necessary for milk synthesis
function of CT in the breast
supports the breast
function of lymph in the breasts
removes waste products
role of the nerves in the breast while Breast feeding
Nerves which makes nipple sensitive and allows baby’s suckling to stimulate the release of hormones necessary for milk ejection reflex and the production of milk
what protect the breasts from injury
Adipose (Fatty) tissue
how do breast change in p
enlarge in size and the development of the mammary function occurs only in pregnancy
where do the breast lie on the chest
Lie generally each side of the midline of the anterior chest wall between 2nd and 6th rib
Lie over the pectoralis muscle, and attached by connective tissue
when dose Breast development start
Development of the breast occurs in the fetus as early as four weeks gestation
where is the mammary ductal system
Inside the bud
how many stages are there to B development
4 stages
what occurs at puberty in the D of B
At puberty the effects of oestrogen and progesterone facilitate further development of the ducts and the glandular system to form the adult breast
when is B development completed
In P due to the Complete development of the mammary function
In puberty what hormones stimulate B development
During puberty , oestrogen and growth hormone stimulate the growth of the mammary ducts
what occurs in the luteal phase (2 phase of M cycle) what happens to the B
In the second half of each menstrual cycle, progesterone stimulates development of the lactiferous ducts and alveoli
what hormone stimulates the development of the lactiferous ducts and alveoli
Progesterone, but only in the luteal phase of menstruation
what pre-determines B size
Genetics
what is the last stage of B development
Breast feeding
what are the The areola
circular middle of the breast, darker pigment so the baby has something to target to feed due to their poor eyesight
location of Montgomery tubercles
on the areola- small little spot like bumps, enlarge in P
function of Montgomery tubercles
small sebaceous glands, secreting oil lie over the areola
They provide lubrication and alter the pH of the skin discouraging the growth of bacteria on the nipple.
how many lobes are there in each B
are 7-10 lobes, divided by bands of fibrous tissue
how many lobules are in each lobe
within each lobe are 20-40 lobules
how many alveoli are in each lobules
Within each lobule are 10-100 alveoli- grape like clusters of glandular tissue
what is the function of the alveoli
Alveoli are composed of milk secreting cells, called acini cells that extract the nutrients necessary for milk production from the network of capillaries which surround each alveolus
what are acini cells
milk secreting cells
location of myoepithelial cells
enclose the alveoli
function of myoepithelial cells
cause the alveoli to contract under the influence of oxytocin
dose the size of the B determine the amount of milk produced
No
function of lactiferous duct
milk drain - milk duct leads to the nipple for feeding
location and function of lactiferous sinus
just under the nipple and areola the lactiferous duct widened to form the lactiferous sinus
F-act as reservoirs for milk during lactation
what causes the expulsion of milk
contraction of the Myoepthilail cells due to oxytocin
in what week do the B undergo changes (enlargement +D)
from week 6
what hormone is responsible for the growth of the lactiferous ducts, and myoepithelial cells, and increased blood flow to the breast
oestrogen
when do the Lactiferous ducts and myoepithelial cells undergo hypertrophy
1st trimester
when is the secretion of colostrum
2 trimester
when do the alveoli mature
3 trimester
in what w is colostrum formed
by W 16
what causes the creation of colostrum
formed under the influence of human placental lactogen (HPL) and prolactin
what hormone allow for the proliferation and enlargement of the alveoli during third trimester
Progesterone, prolactin and human placental lactogen (HPL)
what hormones prevent milk production
High levels of oestrogen and progesterone prevents milk production
what hormone causes the growth of the nipple and areola
HPL and prolactin
which hormone Inhibition of lactation and milk secretion
progestrone
which hormone causes milk synthesis
increased levels of prolactin
what is Lactogenesis
the initiation of milk production involving a complex interaction of hormones and other factors.
occurs-Following delivery of the placenta, oestrogen progesterone and human placental lactogen levels fall abruptly allowing a rise in prolactin and oxytocin levels.
High levels of prolactin secreted by the anterior pituitary gland stimulates the acini cells to produce milk
how many stages are there to Lactogenesis
3
what occurs in Lactogenesis 1
I occurs at 15–20 weeks gestation. This stage is hormonally driven
Colostrum production begins midway through the pregnancy.
what occurs in Lactogenesis 2
occurs 30–40 hours after birth.
It is initiated by the birth of infant plus removal of the placenta.
This stage is also under endocrine control and will occur in all women immediately after birth.
Most women will feel increased breast fullness after Lactogenesis II, generally anywhere between 50 and 73 hours
what occurs in lactogenesis 3
occurs and continues only with ongoing milk production (galactopoesis).
Unlike the first two stages, lactogenesis III is under autocrine control, and is driven by milk removal
name some similarities between the first two stages of lactogenesis
are hormonally driven and under autocrine control
name some differences of the 3 stage of lactogenesis
lactogenesis III is under autocrine control, and is driven by milk removal- differs from 1 and 2 which are homrome driven and autocrine controlled
which hormones decrease and increase after birth
oestrogen and progesterone decline → rise in prolactin and oxytocin
which hormone stimulates acini cells
Prolactin (released from anterior pituitary gland) stimulates acini cells to produce milk
which hormone causes contractions in the Myoepthilial cells
Oxytocin stimulates contraction of myoepithelial cells surrounding alveoli, causing ejection reflex → lactiferous ducts → lactiferous sinus
what occurs when the baby is suckling
When baby suckling, prolactin-releasing hormone is released by the hypothalamus → prolactin released from anterior pituitary gland.
prolactin works on supply and demand process
what occurs when the baby stop suckling
When stops suckling, prolactin-inhibiting factor (PIF) is released from hypothalamus → inhibits prolactin supply
location and function of Oxytocin
released from the posterior pituitary via a neurosensory mechanism,
released in a pulsatile manner causing myoepithelial cells surrounding each alveolus to contract forcing milk into the ductal system towards the nipple. “let down reflex”
what can enhance oxytocin
release can be enhanced by things such as hearing a baby crying, thinking about the baby or preparing to breastfeed
what can inhibit oxytocin
can be inhibited by fear, pain, embarrassment, or anxiety by the mother
name some benefits to both B and m of skin to skin contact
1-Calms and relaxes both mother and baby
2-Regulates the baby’s heart rate and breathing, helping them to better adapt to life outside the womb
3-Stimulates digestion and an interest in feeding
4-Regulates temperature
5-Stimulates the release of hormones to support breastfeeding and mothering
name some benefits of skin to skin in NNU to babies
1- improves milk volume to M and contain up-to date antibiotics
2-Improves oxygen saturation
3-Reduces cortisol (stress) levels particularly following painful procedures
4-Encourages pre-feeding behaviour
5-Assists with growth
6-May reduce hospital stay
name 3 compounds of colostrum
Colostrum contains high amounts of secretory IgA, lactoferrin, and oligosaccharides
what is the foremilk
milk produced in first 3-4 days,
Thick and sticky – lower calorific value than breast milk.
High concentration of protective constituents coat the lining of the baby’s immature intestines, and helps to prevent pathogens from invading the baby’s system
what helps prevent food allergies.
Secretory IgA within the colostrum
what is hindmilk
mature milk- produced around day 3-5 due to increase lactose levels, contains more fat
and contains hormones like human growth factors, cortisol, insulin, thyroxine and prolactin
what hormone can suppress continuing milk production
LH
what is continuing milk production relay on
Reliant on maintenance of frequent suckling (to stimulate milk production) and effective removal by baby
what are benefits of breast feeding for the infants
Immune response- protective against things like luekemia, Diabetes
improves IQ,
Psychological impact of bonding
what conditions may breast feeding protect Babies from
Leukaemia
Rotavirus
Necrotising enterocolitis
Respiratory tract infections incl pneumonia
Urinary tract infections
Otis media
also things like-
Insulin Dependent Diabetes (Type 1 and 2)
Topical allergies (excema, asthma and food allergies)
Coronary Heart Disease in later life
Schizophrenia
Irritable bowel / Crohns Disease / Coeliac disease
Reduced risk of childhood obesity
benefits of breast feeding for mothers
Protective against
a number of cancers but specifically breast and ovarian
Reduced risk of diabetes and hyperlipidaemia in later life
Reduced risk of anaemia
Reduced risk of hypertension in later life
Reduced risk of coronary heart disease
Effective for weight management
Protective long term against osteoporosis
Effective as short term method of contraception / family spacing
