For many mamas-to-be, tender breasts are one of the earliest signs of pregnancy, signaling the many big and exciting changes to come. And that’s just the beginning! Your breasts will continue to change throughout your pregnancy. They’ll likely grow a bit bigger, the veins in them will probably become more noticeable, and your areolas might get darker.
But what about breast milk? When does a pregnant woman start producing milk? And what is colostrum and how is it different from milk? Let’s take a look.
In this article: 📝
- When does lactation start?
- What is colostrum in pregnancy?
- When do pregnant women start lactating “proper” breast milk?
When does lactation start?
Lactation is the medical word for the process of producing breast milk, and it happens while your little one is still inside you.
Most mamas will start producing milk between weeks 12 and 18 of their pregnancy.
By then, your breasts are probably starting to feel a bit bigger than normal. This is because both the size and number of your milk glands is increasing.
Your milk duct system will be fully developed at some point during your second trimester, so that you’re ready to feed your baby even if they arrive a little early.
While you’re pregnant, usually during your last trimester, your breasts might start to leak.
Don’t worry, mama, this is totally normal! It’s a good thing, in fact, it means that your body is getting ready to welcome your hungry baby into the world.
You might notice that your breasts leak when your nipples are stimulated, such as when you have sex, or if they rub against your bra while you exercise.
It’s also normal if your breasts don’t leak, by the way, so don’t fret if this isn’t something you experience. You’re just likely to have cleaner bras – win!
If you do leak, you might notice that the liquid is yellow or orange. That’s because it isn’t mature breast milk, but rather something called colostrum.
What is colostrum in pregnancy?
Colostrum is your baby’s superfood.
It’s full of protein and antibodies that do wonderful things for your little peanut, including providing them with excellent nutrition and helping to develop their immune systems.
It can be clear, creamy, white, or even orange in color, and is usually thick and quite sticky.
Colostrum is easy for babies to digest and is very good for their gut. It works as a laxative and helps them to clear their first poop, which is called meconium.
When do pregnant women start lactating “proper” breast milk?
When you feed your baby for the first time (what a thought!), you’ll be feeding them colostrum rather than mature breast milk for the first two to three days.
For some mamas, it might take longer than this, so don’t worry if your body does its own thing.
Every pregnancy, birth, mama, and baby is different.
You might notice when your milk “comes in”, although this is usually a gradual change rather than something that happens quickly.
Your breasts might start to feel fuller, heavier, or more swollen, and your baby might start to behave a little differently when they’re guzzling.
Breastfeeding is an adventure all on its own and (we’ll say it again) everybody’s journey is unique.
Now that you know a little bit more about where your breast milk comes from, you might want to find out more about the next steps.
The blogs below are here to help you, mama:
31 Best Breastfeeding Tips for New Moms
The 411 on Breast Massage
Your Essential Formula Feeding Guide
7 Breastfeeding Positions to Try
Is it Possible to Increase Breast Milk Supply?
A Quick Guide to Pumping
Mastitis: All You Need to Know
How Long Can Breast Milk Stay
Out?
If you find your breasts leaking during pregnancy, it means your body is getting ready to feed your baby. That liquid is colostrum, the perfect first food for your newborn. As your body's hormones work to regulate milk production, you may find drops of colostrum in your bra, most commonly in the final weeks of pregnancy. Leaking nipples are rarely cause for concern, but if you're bothered by them, simply tuck a couple of nursing pads inside your bra and thank your body for doing its job!
What is colostrum?
Colostrum is a high-protein, antibody-rich liquid that your body produces for your newborn. It's sometimes called "foremilk" because it comes in before mature breast milk. Because it's the perfect first food for your baby, it's sometimes called "liquid gold."
Colostrum:
- Provides ideal newborn nutrition
- Protects against infections
- Is easily digested
- Has a laxative effect that helps clear meconium from an infant's gastrointestinal tract (which in turn reduces the risk of jaundice)
- Helps establish a healthy gut microbiome
What does colostrum look like?
iStock
Colostrum looks like a clear, creamy white, yellow, or even orange liquid (orange is due to beta carotene content). It's often thick, though it can be thin, and it's sometimes a little sticky.
“From Colostrum to Breast Milk - 4241” by Amada 44 is licensed under CC BY-SA 3.0
More mature breast milk is more creamy looking and white or bluish-white in color. Mature milk comes in (in greater quantity) around the third or fourth day after giving birth.
When do expecting moms start producing milk?
Pregnant moms start producing small amounts of colostrum as early as three or four months into pregnancy. (You may have noticed your breasts becoming bigger before that, as your milk glands increase in number and size.) Sometime in your second trimester, your milk duct system is fully developed, so that you can make milk for your baby even if he or she arrives early.
Learn more about how your body makes breast milk.
Is it a problem if my breasts leak during pregnancy?
Leaking nipples are not a problem or unusual during pregnancy. Your body is simply getting ready to feed your baby, and your hormones are at work.
Until you give birth, the hormones estrogen and progesterone will keep you from actively producing much milk. But at the same time, the hormone prolactin becomes active, especially during the last trimester. Prolactin helps your body produce milk and is responsible if you leak a little colostrum.
Some women leak a few drops of colostrum as early as the second trimester, but it's more common during the final weeks of pregnancy, if at all. If you do leak, you may notice small yellow or orange dots on the inside of your bra cups.
The leaks can happen at any time, or you may notice your nipples leaking when they're stimulated – during sex, for example, or if they've rubbed against your bra while exercising or walking.
Tell your caregiver if:
- You're leaking more than a few drops of colostrum at a time, or there's a sudden increase in the amount you're leaking.
- There is blood in the colostrum
- The colostrum is thick
None of these are necessarily worrisome, but it's a good idea to check with your doctor because they could be signs of a clogged milk duct.
Is it okay if I don't leak colostrum?
Don't worry if you don't leak any colostrum. That's perfectly normal, too, and your baby will be able to get the colostrum when he or she breastfeeds.
If you're curious, you can probably hand express a little colostrum in your third trimester. While most lactation experts say it's safe to do so, some studies have suggested a possible association with preterm labor and/or mastitis. To be safe, don't express if you have any risk factors for preterm labor. And don't try until you're at least 37 weeks pregnant.
How to cope with breasts leaking during pregnancy
Breast leaks during pregnancy are usually very minor and easy to handle. If they bother you, though, you can tuck nursing pads inside your bra, and avoid nipple stimulation.
Rest assured that if your breasts are leaking during pregnancy, it's a sign that your body is doing exactly what's necessary to get ready for your baby's arrival.
If you plan to breastfeed your baby – and especially if this is your first time breastfeeding – you might enjoy reading our article on getting started breastfeeding. It'll tell you how often to nurse, how to get comfortable, whether you need a special diet, what problems you might encounter, and where to get help.
Learn more:
- Breastfeeding during pregnancy
- Third trimester checklist
- 7 common pregnancy aches and pains
- Third trimester prenatal visits