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What is the Magic of Colostrum?

colostrum golden hour immune properties lactogenesis newborn skin to skin Nov 08, 2023
What is the magic of colostrum?

Colostrum is an amazing and magical substance. 

It not only provides nutrition for your new baby, but also supports their immature immune system. Feeding this type of milk in the early days of life will lead you down a path towards successful breastfeeding. Before you embark on your breastfeeding journey, learn the importance of colostrum for your baby's health and well being. 

Definition and Importance of Colostrum

Colostrum is the first milk produced by mammals.This special milk is thick and yellow. It contains a high concentration of valuable components that are extremely important for newborn babies.

Production of this thick and yellow substance begins during pregnancy and continues for the first few days postpartum. While it is not truly magical, it has some pretty amazing properties that are designed specifically to support your newborn's immune system and nutrition.

In the early days of breastfeeding, colostrum has many benefits for babies. Even though the amounts are small, the impact that it has for a newborn's health reaches far beyond the early days of life. This milk is full of white blood cells that support a newborn's immature immune system. It also contains growth factors that help to close the tight junctions in a baby's gut. Additionally, high-quality colostrum has antimicrobial peptides that aid a newborn to fight off infection causing viruses and bacteria. 

When Does My Body Produce Colostrum?

Production of colostrum begins around 16 weeks gestation and continues through the first few days postpartum. While you may be able to hand express small amounts of milk late in your pregnancy, you will not have large flowing volumes of milk. Your pregnancy hormones suppress milk production. Once you deliver your baby, then the placenta, your pregnancy hormones drop precipitously and signal your breasts to start increasing milk production. 

After the first few days postpartum, the onset of copious milk production begins. This is also known as Lactogenesis stage 2. While colostrum volumes are generally 5-10 mililiters every few hours, copious milk production or "milk coming in" leads to greater volumes. This occurs for most women around day 3-5 postpartum. Transitional milk occurs as colostrum is gradually replaced by mature milk production. 

Mature breast milk is the final stage of breast milk production. It usually occurs around 2-4 weeks postpartum. This type of milk is thinner, bluish-white in color and produced in larger volumes compared to colostrum.

Are Colostrum and Breast Milk Different?

Colostrum differs from mature breast milk in several key ways. It serves a specific purpose in nourishing and protecting newborns in their first few days of life.

One of the most noticeable differences is the physical appearance. Colostrum is thicker and has a sticky consistency compared to the thinner and more watery mature breast milk. Colostrum is also more yellowish in color due to its higher levels of beta-carotene.

In terms of nutrients, colostrum contains higher amounts of certain components than mature breast milk. It is rich in proteins, which are essential for growth and development. Colostrum also contains higher concentrations of zinc, a mineral that aids in immune function and overall health. Additionally, colostrum is packed with immunoglobulins, also known as antibodies, which provide a boost of protection against infections and diseases.

This early breast milk is specifically designed to meet the unique needs of newborns. Its composition supports the development of their immature immune system. In addition, it provides nourishment during their early days of life. The magical properties of breast milk continue to evolve as the baby grows. It amazingly adapts to the baby's needs at all different stages of their growth. 

Benefits of Early Breast Milk

We have looked at some of the properties of colostrum already, but it is important to emphasize all of its benefits. It is important enough for new babies, that even if you decide that you don't want to breastfeed long term, I implore you to consider giving your baby colostrum. 

All women who give birth to a baby will produce breast milk for the first ten days postpartum as the process is entirely controlled by hormones during that period of time. 

Specific Benefits:

  • Rich in antibodies and immune factors that provide a vital boost of protection against infections and diseases. 
  • Contains high levels of proteins
  • Packed with essential nutrients, including zinc
  • Small volume that fits perfectly in a newborn's small stomach
  • Colostrum transitions into mature breast milk 

Preterm Babies and the Importance of Colostrum

For preterm babies, colostrum is particularly important. It helps in their overall health and development. The immature digestive tracts of these infants are not ready for regular food or infant formula. However, colostrum is easily tolerated by their delicate systems and helps to prepare their intestinal walls for future feedings.

In addition to supporting the digestive system, colostrum has many other benefits for preterm babies. Babies who are born prematurely have extremely immature immune systems.  Colostrum protects the baby's mucous membranes by coating them with a specific antibody. This reduces the risk of infections in the respiratory and gastrointestinal tracts. This first milk is also a fantastic laxative agent. It aids in the passage of meconium as well as more mature stools.

Adequate colostrum also supports the newborn with vital nutrients and calories in the early days of life. Amounts of colostrum may vary from feeding to feeding, but often a mother can express about a tsp of colostrum for each feeding. This prevents you from overfeeding a preterm infant and causing them GI distress. 

When Does My Baby Eat Colostrum?

The benefits of colostrum start as early as the first minutes to hour of life. During the golden hour, newborns are placed skin-to-skin on their mother's bare chest or abdomen. This calms the new baby, helps him or her to transition and allows them to find their source of food and comfort. 

Colostrum is highly concentrated. This concentration makes its small volume more impactful for the baby. Despite its minimal quantity, colostrum is packed with essential nutrients. This includes proteins, fats, carbohydrates, vitamins, and minerals. 

This sticky and yellow fluid not only provides nourishment, but it also delivers a powerful boost of immune protection. It is rich in antibodies and immune factors that shield your baby against various infections. Additionally, colostrum provides factors that strengthen and help to mature a newborn's immune system. Colostrum is also essential to create a foundation for a healthy gut. Breast milk supports the growth of beneficial probiotics by feeding the good bacteria in the gut. It also prepares the intestinal cells for future feedings by closing the openings between cells. 

When Does My Milk Change? 

In order to answer this question, it is imperative to understand the different stages of lactogenesis.

  • Lactogenesis I - begins around 16 weeks gestation (pregnancy) and ends about day 3-5 postpartum, lactation is entirely controlled by hormones, colostrum production
  • Lactogenesis II (secretory activation) - begins around day 3-5 postpartum with the onset of copious milk production or "milk coming in" and ends around day 9-10 postpartum, transitional milk production
  • Lactogenesis III- begins around 9-10 days postpartum and ends with involution (weaning), breast milk production is mainly locally controlled at the level of the breast, mature milk production
  • Lactogenesis IV (involution) - occurs about 40 days after breastfeeding for the last time 


Breastfeeding can be a magical experience for new mothers, but it can also be very difficult. I congratulate you for reading about colostrum and all of its amazing properties before you begin down this road. Whether you breastfeed for several months, a year or a few days, you are an awesome mom. 

If you need help to make your breastfeeding plans known to hospital staff, download My Breastfeeding Plan. It is a free check list that you can customize to express your wishes to breastfeed and how you would like to accomplish that goal. 

© 127 Pediatrics; November 2023

This article is for informational purposes only and should not be construed as medical advice.

Dr. Wadley, 127 Pediatrics
Andrea Wadley, MD, IBCLC

Dr. Andrea Wadley is the owner, pediatrician, and breastfeeding medicine specialist for 127 Pediatrics. She has an established house-calls only pediatric practice in Colleyville, TX. She is also the owner and operator of the 127 Pediatrics Online Breastfeeding Medicine and Education Center.


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