Changes in Mom

You spend 9 months adapting to the changes in your body due to your pregnancy, and once your baby is born, your body starts changing again.

During pregnancy, your mammary glands change as a result of a wide range of hormones, including estrogen, progesterone and prolactin. Towards the end of your pregnancy, your body starts producing colostrum, a special milk that is important to your baby in his first few days of life.

Within a few days after giving birth, your mature milk will “come in.” Your breasts will become engorged as they swell with milk, becoming extremely full and firm.

Your milk will “come in” whether you breastfeed or not, but continued milk production only occurs if you empty your breasts of the milk regularly via breastfeeding or through using a breastpump. Your breastmilk production is depended on your body’s production of 2 key hormones: oxytocin and prolactin.

Oxytocin: The “Cuddle Hormone”

As your baby nurses, your body produces oxytocin, a hormone that impacts your body in a number of ways. First of all, oxytocin triggers the milk ejection reflex, also known as “letdown”. Some moms actually feel the milk letdown happening as the cells around your milk glands contract and squeeze the milk out.

Oxytocin released during breastfeeding or breastpumping also helps the uterus contract and return to its normal size and shape.

Finally, oxytocin is considered a socializing hormone that helps us form relationships with others. Oxytocin is produced by both mom and baby, and is further transferred to baby in mom’s breastmilk. It is stimulated by either breastfeeding or breastpumping and skin-to-skin contact. Oxytocin is also produced in dads when they play with their baby and have skin-to-skin contact, and helps dad bond with baby too.


Prolactin is another important hormone in breastmilk feeding. You start producing it during your pregnancy, but high levels of estrogen and progesterone in your bloodstream counteract its effects. When you give birth, the levels of estrogen and progesterone suddenly drop off. That’s when prolactin can start doing its job and stimulate the production of breastmilk.

It is the levels of prolactin in the body that allow breastmilk feeding to continue. That is why it is so important to initiate breastmilk feeding within 30 minutes to an hour after your baby is born. Prolactin levels drop between feedings, but every time your baby nurses, or you pump, the levels increase, signaling the body to make more breastmilk.

Types of Breastmilk


A low-fat, high-protein, yellowish milk full of antibodies, leukocytes, stem cells, and a myriad of other things that coat and protect baby’s digestive tract. Colostrum is produced in very small, concentrated quantities to accommodate the tiny tummies of newborn infants. Besides providing nutrition and protecting baby from infections, colostrum’s laxative properties also help him to pass his first stools.

In fact, colostrum is so complex that we are still just scraping the surface when
it comes to discovering all of its amazing properties and benefits for babies.

Once your milk has come in, the mature breastmilk you produce can be divided into 2 distinct types: foremilk and hindmilk.

Your breasts don’t actually produce 2 different kinds of milk; however, the fat content in the milk depends on how long the milk has been sitting in the ducts.

Foremilk: Thinner and Low in Fat

When your baby starts nursing he receives the lower-fat, higher-lactose foremilk. This milk is important for quenching your baby’s thirst and providing him with the energy he needs now.

Hindmilk: Thicker and High in Fat

As a breastfeeding session on one breast continues, your baby will start to receive the high-fat hindmilk that keeps him feeling full and provides the energy he needs to grow.


Types of Breastmilk

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