Colostrum is the first form of breastmilk that is released by the mammary glands after giving birth. It's nutrient-dense and high in antibodies and antioxidants to build a newborn baby's immune system. It changes to breast milk within two to four days after your baby is born. Colostrum is thicker and more yellow than traditional breast milk.


What is colostrum?

Colostrum (kuh-loss-trum) is the first milk your body produces during pregnancy. It forms in your mammary glands (breasts) and plays an important role in building your baby's immune system. If you plan on breastfeeding (nursing or chestfeeding), it's the first milk your baby will get from your breasts. If you don't want to breastfeed or if your baby is struggling to breastfeed, you can hand express colostrum. It's high in protein, vitamins, minerals and immunoglobulins (antibodies) that help build your baby's immune system. It's often called "liquid gold" because of its rich, golden color and valuable benefits.


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What is colostrum made of?

Colostrum is high in protein and low in fat and sugar. It's filled with white blood cells that produce antibodies. These antibodies strengthen your baby's immune system, protecting him or her from infection. Colostrum is highly concentrated and nutrient-dense even in tiny doses, so your baby's tummy doesn't need a lot to reap its benefits.

What kind of nutrients are in colostrum?

Colostrum is rich in nutrients that protect and nourish your baby unlike anything else. It's made up of things like:

  • Immunoglobulin A (an antibody).
  • Lactoferrin (a protein that helps prevent infection).
  • Leukocytes (white blood cells).
  • Epidermal growth factor (a protein that stimulates cell growth).

It gets its color from carotenoids (an antioxidant) and vitamin A. Vitamin A plays a vital role in your baby's vision, skin and immune system. Colostrum is rich in magnesium, which supports your baby’s heart and bones, and copper and zinc, which also support immunity.

What's the difference between colostrum and breast milk?

Colostrum is a nutrient-rich first milk produced by your breasts during pregnancy. It changes to transitional breast milk a few days after your baby is born. However, small amounts of colostrum remain in your breast milk for several weeks.

There are distinct differences between colostrum and breast milk:

  • Colostrum is filled with immunoglobins to boost your baby's immune system and protect it from illness.
  • Colostrum has two times as much protein.
  • Colostrum has four times as much zinc.
  • Colostrum is lower in fat and sugar so it's easier to digest.
  • Colostrum is thicker and more yellow.

What are the stages of breast milk?

There are three different stages of breast milk: colostrum, transitional milk and mature milk.

  • Colostrum: Your first milk that lasts between two and four days after birth.
  • Transitional milk: Begins approximately four days after birth and lasts about two weeks.
  • Mature milk: Milk that lasts from approximately 14 days after birth until you are done producing milk.


When does colostrum turn to milk?

After approximately three or four days, colostrum will turn to transitional milk. This is often referred to as someone's milk "coming in." Your breasts will feel firm, tender and full. It means your milk supply has ramped up. By this time your baby's stomach has expanded and they can drink more milk each feeding. Once your milk supply is established and your body has stabilized, transitional milk changes to mature milk.

What makes colostrum turn to breast milk?

The pregnancy hormones created by the placenta help you create colostrum. The hormone progesterone drops significantly when the placenta separates from your uterus (after your baby is born). This drop in progesterone triggers your breasts to create milk.


What is the purpose of colostrum?

The function of your breasts, or mammary glands, is to produce milk to feed your baby. Colostrum is more than the first milk your baby consumes after birth. It's highly concentrated with nutrients and antibodies to fight infection and protect your baby. It provides a powerful, unique immunity that only it can provide. Because your baby only needs a little bit of colostrum, it also helps them learn to suck, swallow and breathe during feeding.


What are the benefits of colostrum?

Colostrum builds your baby's immune system and provides concentrated nutrition. Some of the benefits of colostrum are:

  • Helps strengthen your baby's immune system.
  • Helps to establish a healthy gut by coating the intestines. This helps keep harmful bacteria from being absorbed.
  • Offers ideal nutrition for a newborn.
  • Has a laxative effect that helps your baby clear meconium (your baby's first poop) and lessens the chance of jaundice.
  • Easy to digest.
  • Helps prevent low blood sugar in full-term babies.

Why is colostrum good for newborns?

Colostrum has all the nutrients your baby needs in the first few days of life. It's also packed with nutrients and vitamins to strengthen your baby's immune system.

The flow of colostrum from your nipples is slow so your baby can learn to breastfeed (nurse). Learning how to breastfeed takes practice and requires your newborn to not only learn to suck and swallow but breathe at the same time.

Does leaking colostrum mean labor is close?

Colostrum leaking from your breasts doesn't mean labor is coming. Leaking colostrum is normal and some people notice it as early as the second trimester. Some don't notice any signs of leaking colostrum while others will see dried colostrum on their nipples. If you are leaking colostrum, you can wear disposable or washable breast pads.

Can you express colostrum if you're pregnant?

Colostrum can be expressed by about week 37 in pregnancy and is beneficial for some people. Using your hands to compress your breasts in a rhythmic pattern so that milk comes out is called hand expressing. Expressing colostrum before your baby is born carries some risks like contractions or premature labor. It can be beneficial to those at risk for premature birth, low milk supply or when certain health conditions present.

Speak with your healthcare provider before you remove colostrum from your breasts. If you are leaking colostrum, it may be safe to collect and store it for when your baby is born.

Can you pump colostrum?

It's difficult to pump colostrum with a breast pump because of its thick consistency. Most people recommend and prefer using their hands to express colostrum. Hand expressing colostrum usually produces more colostrum than a pump.


What does colostrum look like?

Colostrum is often a deep, rich yellow or orange color, almost like the yolk of an egg. This is because it contains high levels of beta carotene. It can sometimes appear white, clear or creamy. It's a thicker consistency than breast milk (or cow's milk), but the thickness varies from person to person. Colostrum is often sticky and can contain faint traces of blood (this is normal).

How do I know I am making colostrum?

Your body begins producing colostrum between 12 and 18 weeks in pregnancy. Most people will produce anywhere from a tablespoon to an ounce of colostrum within the first 24 hours of delivery. This slowly increases until transitional milk comes in around the third or fourth day. In most cases, you will not know if you are making colostrum, however, it's very rare to be unable to produce colostrum. You will know if your baby is getting colostrum if he or she is maintaining their weight and wetting diapers.

How long do you have colostrum?

Your body produces colostrum for up to about five days after your baby is born. It changes to transitional milk around this time, then changes again to mature milk after about 14 days. Traces of colostrum are present in your breast milk for up to six weeks.

Conditions and Disorders

What happens if you don't produce colostrum?

Most people will produce some colostrum — not producing it is rare. It's normal to feel like nothing is coming out of your breasts and worry that your baby isn't getting enough. Your baby only needs a few teaspoons of colostrum to fill their tiny stomach.


How do you store pumped colostrum?

If you and your healthcare provider decide it's safe to express and store colostrum, there are a few rules to follow. First, you should ensure the colostrum is stored in a sterile container or syringe. It can be kept in your refrigerator for about two or three days. It must be moved to a freezer after three days. Colostrum can be kept in a freezer for at least three months.

Additional Common Questions

How much colostrum does a newborn need?

Your newborn's tummy is about the size of a marble. They only need about an ounce of colostrum per day. This equals about a teaspoon each feeding (you can expect to feed your newborn eight to 10 times the first few days). The amount of colostrum (and then transitional milk) your baby needs increases slowly each day as their stomach expands. As your body transitions to producing regular breast milk, your milk production will increase to meet their needs.

Do I need to supplement?

No, you shouldn't need to supplement. A tiny bit of colostrum goes a long way in filling up your baby. Check with your healthcare provider to make sure your baby is gaining weight. If your baby is wetting diapers and seems pretty happy, supplementing is usually not necessary.

Is it okay to squeeze out colostrum?

Yes, it's usually OK to squeeze out colostrum once you reach full-term pregnancy (37 weeks). Check with your healthcare provider if you wish to do this prior to your baby being born. If you want to hand express colostrum for your newborn, follow these steps:

  • Cup your breasts with your hand in a "C" shape. Four fingers should be under your breast and your thumb should be above your nipple.
  • Use your thumb and index finger to gently squeeze your areola and nipple.
  • Repeat several times and in a pattern. Apply firm pressure but do not slide your fingers. If colostrum doesn't come out, try moving your fingers to another spot.
  • Colostrum should slowly flow out within minutes. It's thick and comes out in drops.
  • You can repeat this a few times per day.

Please note that expressing colostrum before your baby is born carries risks. Some people can go into premature labor or begin having contractions. Talk to your healthcare provider before you express colostrum.

A note from Cleveland Clinic

Colostrum is the first milk produced by your breasts. It's rich in nutrients and high in antibodies and antioxidants. Getting started with breastfeeding can be difficult and usually requires assistance, so don't be ashamed to ask your healthcare provider for help. Breastfeeding early and often is the best way to make sure your baby gets the many benefits from colostrum. Hand expressing colostrum and feeding your baby with a syringe is also an option. Ask your healthcare team for help if feeding your baby colostrum is something you wish to do.

Medically Reviewed

Last reviewed on 02/21/2022.

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