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When Does Milk Come in During Pregnancy?

If your body is producing all the hormones needed to induce the production of breast milk, you can start producing breast milk halfway through your pregnancy. At this time, your breast milk production is hormonally driven and not yet a supply and demand process that activates when your baby starts breastfeeding.

Once you give birth to your baby, your body’s prolactin levels increase. The hormone prolactin properly initiates milk production.

A fascinating fact about breast milk is that it can also be made by women who have never been pregnant or have reached menopause. This is called induced lactation, and it is a process that allows the woman’s body to mimic the changes experienced in pregnancy so that she can create the necessary hormones that tell her body to produce breast milk.

Breast Milk is also produced according to your baby’s demand. If your baby breastfeeds a lot, your body will produce a lot of breast milk to meet their demand and nutritional needs. If your baby doesn’t breastfeed enough, your body will produce a limited amount of breast milk. This is why mothers whose babies are not breastfeeding well at first, or mothers who adopt a baby or have a surrogate carry their child are encouraged to pump their breast milk as often as possible. Pumping breast milk mimics feeding your baby, and it sends a message to your body that there is a demand for breast milk, which your body meets by creating more.

Breast Milk also differs according to your baby’s growth stage. The breast milk produced for a premature baby differs from the breast milk produced for your newborn, and that differs from the breast milk produced for your six-month-old. It still contains all the necessary and essential nutrients, but they are suited to your baby’s current growth stage. Your body customizes it to meet your baby’s needs.

How your body creates breast milk

Your endocrine system is the system that controls the hormones in your body and controls breast milk production during pregnancy and the first few days after you give birth.

Your body can start producing milk as early as halfway through your pregnancy if all the proper hormones are being produced. This first breast milk is called colostrum, and this first stage of breast milk production is called Lactogenesis I.

Your body will be producing colostrum during the last few months of your pregnancy, but the high levels of progesterone will stop milk secretion and keep the amount of milk your produce to a minimum. This is why you may have little spills or sometimes not even notice you produced milk.

Once you give birth, your placenta is expelled from your body, and the production of hormones that it activated to keep it in place progesterone, estrogen, and HPL drops, which leads to higher levels of prolactin, which is the hormone that tells your body to produce breast milk. Prolactin leads to Lactogenesis II, the next stage of milk production called copious milk production. This process activates approximately 30 – 40 hours after giving birth, and mothers will not typically feel the fullness of their breasts with milk until 2 – 3 days after the birth of their baby.

The last stage of milk production is Lactogenesis III, which is the maintenance stage or the supply and demand stage. At this stage, your body switches from endocrine or hormone control of milk production to local control, which means that the production of breast milk is controlled at your breast. The more your baby breastfeeds, the more milk you will produce, and the less they breastfeed, the less milk you produce.

The process of milk production will continue as long as the milk is removed from your breast, either by your baby or a breast pump.

Factors that affect breast milk production

The production of breast milk is controlled by prolactin. This hormone has to be present for your breast to produce any breast milk.

Breast Milk synthesis is controlled by a whey protein called Feedback Inhibitor of Lactation(FIL). It is in charge of slowing down the synthesis of breast milk when the breast is full or hastening it when the breast is empty. Breast milk production speeds up when the FIL is not present. Its presence slows down the production of breast milk.

The fat content of your breast milk is also affected by how much milk your breasts contain. The more milk you have, the less fat is made for the milk. The less milk you have, the more fat is added to the milk. You can use this information to tailor your breast milk for your baby’s needs by pumping to empty your breasts so that you can have a fattier or creamier store for your baby’s next feeding session. Fat is important for your baby’s proper brain and body development.

Breast Milk production throughout the day

Research shows that breast milk production increases during morning hours and gradually fall throughout the day. Research also shows the fat content in breast milk increases throughout the day. This is in line with the emptier breast having more fat content. Fat is important for your baby’s proper brain development.

Increasing your breast milk production

If you wish to increase your breast milk production, it is important to keep your breasts empty throughout the day. Doing so will ensure that the fat content produced by your breasts is higher, and your breasts are producing milk to be filled.

You can accomplish this by emptying your breasts after each nursing session using your breast pump. You should increase the nursing sessions with your baby to 1.5hrs – 2hrs apart.
Keeping your breasts empty will help your body produce the highest quality of milk and produce it quickly to meet your baby’s demand.

You will know your breasts are empty when they are adequately soft. Then the FIL will decrease, and your body will produce more milk faster.


Mothers who see an oversupply of milk can reduce production without weaning your baby or decreasing your baby’s nursing by nursing your baby at one breast for more than 4 hours so that milk accumulates at the other breast, activating the FIL, which slows down milk production at the breast that is not being used.

You are essentially keeping one breast full, which will slow down its milk production, while your baby nurses at one breast, which will empty and keep producing milk. That is fascinating.

Breastfeeding is a special time to focus on bonding with your baby. It is the true definition of Mommy and me time. It is important to remove all stressors and only focus on being in love with your baby and how much you love nursing them. A calm and positively affirmed breastfeeding environment will help your body easily produce milk for your baby. When you have stressed out, your body produces cortisol, a hormone that essentially blocks all other processes because its focus is to keep you alive, and all other processes, including breastfeeding, become non-essential and are suspended indefinitely.

It is important to avoid all stressors.

1 thought on “When Does Milk Come in During Pregnancy?”

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