How Breast Milk Is Made

 How Breast Milk Is Made

If you've every been pregnant or if you are pregnant

now, you've probably noticed a metamorphisis in your

bra cups.  The physical changes (tender, swollen 

breasts) may be one of the earliest clues that you

have conceived.  Many experts believe that the color

change in the areola may also be helpful when it

comes to breast feeding.

What's going on

Perhaps what's even more remarkable than visible

changes is the extensive changes that are taking 

place inside of your breasts.  The developing 

placenta stimulates the release of estrogen and 

progesterone, which will in turn stimulate the 

complex biological system that helps to make lactation

possible.

Before you get pregnant, a combination of supportive

tissue, milk glands, and fat make up the larger

portions of your breats.  The fact is, your newly

swollen breasts have been preparing for your 

pregnancy since you were in your mother's womb!

When you were born, your main milk ducts had already

formed.  Your mammary glands stayed quiet until

you reached puberty, when a flood of the female

hormone estrogen caused them to grow and also to

swell.  During pregnancy, those glands will kick

into high gear.

Before your baby arrives, glandular tissue has 

replaced a majority of the fat cells and accounts

for your bigger than before breasts.  Each breast

may actually get as much as 1 1/2 pounds heavier

than before!

Nestled among the fatty cells and glandular tissue

is an intricate network of channels or canals known

as the milk ducts.  The pregnancy hormones will 

cause these ducts to increase in both number and

size, with the ducts branching off into smaller

canals near the chest wall known as ductules.

At the end of each duct is a cluster of smaller

sacs known as alveoli.  The cluster of alveoli is

known as a lobule, while a cluster of lobule is

known as a lobe.  Each breast will contain around

15 - 20 lobes, with one milk duct for every lobe.

The milk is produced inside of the alveoli, which

is surrounded by tiny muscles that squeeze the

glands and help to push the milk out into the

ductules.  Those ductules will lead to a bigger

duct that widens into a milk pool directly below

the areola.

The milk pools will act as resevoirs that hold the

milk until your baby sucks it through the tiny 

openings in your nipples.  

Mother Nature is so smart that your milk duct

system will become fully developed around the time

of your second trimester, so you can properly 

breast feed your baby even if he or she arrives

earlier than you are anticipating.