breast committee

1. +
Physiology
of the breast
Dr. Kawita Bapat
BREAST COMMITTEE FOGSI

2. +
Tanner Staging

3. +
Effect of estrogen and progesterone on
breast
Estrogen Progesteron
1. Growth of mammary
glands
2. Deposition of fat in the
breast
1. Additional growth of
lobules
2. Budding of alveoli
3. Secretory changes just
like in the endometrium

4. +
Cyclical changes of breasts
during menstrual cycle

5. +
Changes during pregnancy
 Ducts grow and branch;
 breasts enlarge to twice their normal weight
 increase in mammary blood flow leads to vascular
engorgement
 The areola of the nipples pigmentation and diameter
increases.
 The Montgomery's glands enlarge and tend to protrude.
 By the 16th week (2nd trimester) the breasts begin to produce
colostrum

6. +
Changes during lactation

7. + Prolactin
 The hormone prolactin promote milk secretion
 During pregnancy the hormone concentration in blood rises
steadily from the 5th week of pregnancy until birth of the baby
 At full term prolactin level rises to 10 to 20 times the normal
non pregnant level.
 Acini become dilated and engorged with colostrum and then
milk.

8. +
Prolactin
After birth:

9. +
Oxytocin
 Sensory impulses via somatic nerves from the nipples to
hypothalamus and posterior pituitary- release of oxytocin and
prolactin
 The oxytocin causes myoepithelial cells to contract
 milk is expressed from the alveoli into the ducts at a pressure of
+10 to 20 mm Hg.
 Suckling on one breast causes milk flow not only in that breast but
also in the opposite breast.
 Fondling of the baby by the mother or hearing the baby crying
often gives enough of an emotional signal to the hypothalamus to
cause milk ejection.

10. +
Menopause
 Lobules begin to recede
 Mostly ducts adipose tissue and fibrous tissue
 Histologically postmenopausal and prepubertal breasts are
very similar.
 Hormone therapy may delay postmenopausal changes in the
breast and mimic a more active physiologic or premenopausal
state (ie cyclic tenderness due to increased nodularity etc).