Colostrum: What Is It, Benefits & What To Expect

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), 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:

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• 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.