1. Lactogenesis and Composition of Breast Milk

2. A. Embryologically: belong to integument
I. General Information
A. Embryologically: belong to integument
B. Functionally: part of reproductive system
C. Modified apocrine sweat glands

3. Position and Attachment 1. Lateral aspect of pectoral region
II. Anatomy
Position and Attachment
1. Lateral aspect of pectoral region
2. Located between ribs 3 and 6/7
3. Extend form sternum to axilla
4. Surrounded by superficial fascia
5. Rest on deep fascia

4. Breast Anatomy

5. a. Changes with hormonal signals b. Onset of menstruation
Structure, continued …
Secretory epithelium
a. Changes with hormonal signals
b. Onset of menstruation
c. Pregnancy (glands begin to enlarge at 2nd month)

6. 1. Arteries: derived from thoracic branches
Structure, continued …
Vessels & Nerves
1. Arteries: derived from thoracic branches
a. Axillary arteries
b. Internal mammary arteries c. Intercostal arteries

7. Vessels & Nerves, continued …
Veins
a. form a ring around the base of the nipple (“circulus venosus”)
b. External mammary v to axillary v
c. Internal mammary v to subclavian v

8. a. anterior & lateral cutaneous nerves of thorax
Breast Anatomy, con’t…
Nerve Innervation: derived from:
a. anterior & lateral cutaneous nerves of thorax
b. spinal segments T3 – T6

9. Lymphatics Subclavian nodes Axillary nodes Parasternal nodes
Lateral pectoral nodes

10. Lactation: four stages
Mammogenesis
Lactogenesis
Galactokinesis
Galactopoiesis

11. Growth of ducts and lobuloalveolar systems
Mammogenesis
From 24th week of pregnancy
Growth of ducts and lobuloalveolar systems
Hormonal influences-
estrogen, adrenal steroids, progesterone, estrogen, prolactin, adrenal steroids and growth hormone

12. Lactogenesis I Lactogenesis II Begins during pregnancy
Alveoli distend with colostrum
Lactogenesis II
Initiation of significant milk secretion at or just after parturition- colostrum
Mature milk secretion begins hours postpartum and averages 1-2 ml/g of breast tissue /day

13. Lactogenesis III
Milk supply is more firmly established- autocrine control system begins
More the milk is removed from the breasts, more the breast will produce milk

14. Galactokinesis
Ejection of Milk
Suction exerted by the baby during suckling
Contractile mechanism
Draught sensation

15. Lactation Reflex

16. Galactopoiesis
Maintenance Of Lactation
Prolactin
Sucking

17. Composition of Breast Milk (gms/100ml)
Sugar : 7
Fat : 3.5
Protein : 1.2
Minerals : 0.4
Water : 89
Calories : 67

18. ‘Breast fed infants, are Healthy Infants’

19. THANK YOU