Breast Development and Physiology Flashcards
Breast feeding has been shown to lead to what benefits for the mother?
- Decreased postpartum bleeding
- More rapid uterine involution
- Earlier return to pre-pregnancy weight
The AAP recommends exclusive breast feeding for ______________.
all children for the first six months
Breast feeding has been shown to decrease what negative outcomes in neonates?
- Meningitis
- Diarrhea
- Bacteremia
- URIs
- UTIs
- Sepsis
- SIDS
- OM
- Diabetes
- Leukemia/lymphoma
Describe the structure or the breast.
Breasts are divided into lobes that contain milk-producing alveoli. These are surrounded by myoepithelium that pushes milk into the conducting ductules that ultimately lead to one duct.
The bumps on the areolae are called ______________.
glands of Montgomery
What changes in composition occur during lactation?
A much greater percentage of the breast becomes glandular and a much less percent of the breast is intraglandular fat
Prior to puberty, the ductules lead to __________.
terminal limb buds in the breast (that have not differentiated into glands)
What embryologic structures give rise to the breast?
The ectoderm dives into the underlying mesoderm
What protein induces differentiation of the mammary mesenchyme?
Parathyroid hormone-related protein (PTHrp)
Note: even the nipple is dependent on the development of the mesenchyme, so mutations in PTHrp can lead to agenesis of the nipple.
What is witch’s milk?
Elevated prolactin and progesterone levels in pregnancy can pass into neonates and cause transient neonatal lactation.
Which hormones stimulate the development of ducts and alveoli?
- Ducts: LH (terminal end buds)
* Alveoli: progesterone (side branching and TDLU development)
Increased _______________ during puberty induces the elongation and branching of the ductal network by increasing IGF-1 production by stromal cells.
estrogen and GH
_______________ regress at the end of the luteal phase unless pregnancy occurs.
TDLU
Milk secretion is initiated by _______________.
the fall in progesterone that occurs when the placenta is removed
Why does suckling induce milk secretion?
suckling inhibits hypothalamic dopamine release, this allows prolactin to be released from the anterior pituitary to cause milk secretion .
