Colostrum – General
What is colostrum?
Colostrum is produced from before birth through the first few days of life. It is followed by transitional milk, a mix of colostrum and mature milk, and then by mature milk, from about the second week after birth.
Breasts start producing colostrum somewhere between 12 and 20 weeks of pregnancy. You may or may leak colostrum in the last half of pregnancy. Whether colostrum leaks or not has no relationship to milk production.¹
Colostrum is often thick and sticky. It is usually yellow (or orange) but can also be clear or white. The yellow color is due to beta-carotene, an antioxidant present in colostrum. Colostrum is measured in drops or teaspoons – perfect, small feedings for the small stomach your baby has at birth. It is easily digested.
Why is colostrum important for your baby?
Although there are only small amounts of colostrum available at birth, it is the perfect food for babies in the first few days of their lives. At the same time, colostrum develops your baby’s immune system and feeds the good bacteria in your baby’s gut. Immune factors are transferred from you to your baby through colostrum.
The importance of colostrum has not always been recognized in some cultures leading to “colostrum taboos” in the first three to five days after birth. These taboos are less common today, but may still be encountered, see Colostrum Through a Cultural Lens.
Research tells us that colostrum in the first few days of life is a unique opportunity to develop a strong immune system and gut microbiome. It is a superfood.² ³
Compared to mature milk made later (starting about the second week after birth), colostrum has:
Colostrum acts as a laxative to help your baby pass meconium. Meconium is the black, tarry stool that the baby passes in the first few days of life. Passing meconium helps prevent jaundice. If your baby is not having a bowel movement each day in the first few days, or if their stool is not turning yellow, yellow-green, tan or occasionally green by day four, please talk to a La Leche League Leader or your baby’s healthcare provider. Lack of stooling can be an indicator of a feeding issue that needs to be addressed.
If you have diabetes or another risk factor to milk coming around the third day, you may want to consider collecting colostrum prior to birth.
The colostrum and early milk mothers make for their preterm baby are very different from the colostrum and early milk made for a full-term baby. Preterm colostrum has the same disease protection – through antioxidants, antibodies and immunoglobulins (immune factors) – as term colostrum. However, because it has more of these components, it is even more powerful. This superfood reduces inflammation in the gut of a preterm baby and can prevent necrotizing enterocolitis (NEC), which can damage the gut lining in early preterm babies. Preterm babies receiving their own mother’s colostrum have significantly better health outcomes, in the short-term and in the long-term.⁶
First Meals
Colostrum is waiting for your baby at birth. Nursing in the first hour will yield colostrum that is protective and satisfying for your baby. Remember that your baby’s stomach is tiny at birth, see First Few Days of a Breastfed Baby, so a large feeding may look very small! Learning to suck and swallow milk is easier in small amounts.
If for some reason your baby cannot nurse in the early hours, hand express the colostrum so it can be fed to your baby. Hand expressing colostrum almost always yields more volume than using a breast pump in the early days.⁷ Relying on pumping colostrum means you may not have any for your baby because it will all be left stuck to the pump flanges!
The first day, babies usually drink about 30 ml (about an ounce), divided over several feedings. The amount your baby drinks will be increasing each day. On day four, babies usually take 30-60 ml (one to two ounces) per feeding. This volume will slowly increase to about 700 ml (23 ounces) or more per day. Your colostrum will prepare your baby for the larger feeds ahead, and will fill the tiny stomach, as your own milk will be gradually increasing in amount each day. This will gently stretch your baby’s stomach over the first week. By the fourth day, most babies will be drinking colostrum mixed with more mature milk. There is a gradual transition from colostrum to mature milk.⁷,⁸
Colostrum is the most important first food for all infants. Although it is available only in small amounts, it is a powerful superfood!
References:
¹ Marsha Walker, Breastfeeding Management for the Clinician: Using the Evidence, (Jones & Bartlett, 2023),.21, 94, 95.
² Marsha Walker, Breastfeeding Management for the Clinician: Using the Evidence, (Jones & Bartlett, 2023), 21.
³ O Ballard and AL Morrow, “Human milk composition: nutrients and bioactive factors”. Pediatr Clin North Am, 60(1) (Feb 2013): 49-74, doi: 10.1016/j.pcl.2012.10.002. PMID: 23178060; PMCID: PMC3586783.
⁴ Ruth A. Lawrence and Robert M Lawrence. Breastfeeding: A Guide for the Medical Profession (Elsevier. 2022).
⁵ Sy Kim and DY Yi, “Components of Human Breast Milk: From Macronutrient to Microbiome and MicroRNA”, Clinical Experiences in Pediatrics; 63(8) (Aug 2020): 301-309. PMID:32252145;PMCID:PMC7402982. https://pmc.ncbi.nlm.nih.gov/articles/PMC7402982/
⁶ Marsha Walker, Breastfeeding Management for the Clinician: Using the Evidence, (Jones & Bartlett, 2023), 376-377.
⁷ Academy of Breastfeeding Medicine, Clinical Protocol #3: Supplementary Feedings in the Healthy Term Breastfed Neonate, Revised 2017. ABM Clinical Protocol #3: Supplementary Feedings in the Healthy Term Breastfed Neonate, Revised 2017
⁸ Lawrence and Lawrence, Breastfeeding: A Guide for the Medical Professional, (Elsevier. 2022), 100.
Resources:
Maya Bolman, The Basics of Breast Massage and Hand Expression. https://www.mayabolman.com/videos/v/basicsofbreastmassage
Colostro, article from La Leche League Italia “Colostrum”
First Few Days of a Breastfed Baby, published by LLL Asia & Middle East, adapted from Ligue La Leche
Hand Expression
The Power of Hand Expression, article from La Leche League International
ЛЛЛБГ, ЛЛЛ България: Наука за майчиното мляко, article from La Leche League Bulgaria “Breastmilk Science”
Ла Лече Лига Россия: Что такое молозиво?, article from La Leche League Russia “What is colostrum?”
Published May 2026.
*Adapted from La Leche League International information.
Colostrum is produced from before birth through the first few days of life. It is followed by transitional milk, a mix of colostrum and mature milk, and then by mature milk, from about the second week after birth.
Breasts start producing colostrum somewhere between 12 and 20 weeks of pregnancy. You may or may leak colostrum in the last half of pregnancy. Whether colostrum leaks or not has no relationship to milk production.¹
Colostrum is often thick and sticky. It is usually yellow (or orange) but can also be clear or white. The yellow color is due to beta-carotene, an antioxidant present in colostrum. Colostrum is measured in drops or teaspoons – perfect, small feedings for the small stomach your baby has at birth. It is easily digested.
Why is colostrum important for your baby?
Although there are only small amounts of colostrum available at birth, it is the perfect food for babies in the first few days of their lives. At the same time, colostrum develops your baby’s immune system and feeds the good bacteria in your baby’s gut. Immune factors are transferred from you to your baby through colostrum.
The importance of colostrum has not always been recognized in some cultures leading to “colostrum taboos” in the first three to five days after birth. These taboos are less common today, but may still be encountered, see Colostrum Through a Cultural Lens.
Research tells us that colostrum in the first few days of life is a unique opportunity to develop a strong immune system and gut microbiome. It is a superfood.² ³
Compared to mature milk made later (starting about the second week after birth), colostrum has:
- More growth factors, which promote cell and tissue repair.
- More human milk oligosaccharides (HMOs). HMOs are indigestible complex sugars that act as a prebiotic feeding the good bacteria in the gut. They help to grow a healthy gut microbiome. Good bacteria can help seal the baby’s gut. They help keep inflammation levels low and prevent infection. They contribute to overall good health.
- Higher amounts of fat-soluble vitamins. Vitamin A can be three times higher in colostrum than in mature milk. Carotenoids (antioxidants) can be 10 times higher. Vitamin E can be two to three times higher than mature milk.⁴,⁵
Colostrum acts as a laxative to help your baby pass meconium. Meconium is the black, tarry stool that the baby passes in the first few days of life. Passing meconium helps prevent jaundice. If your baby is not having a bowel movement each day in the first few days, or if their stool is not turning yellow, yellow-green, tan or occasionally green by day four, please talk to a La Leche League Leader or your baby’s healthcare provider. Lack of stooling can be an indicator of a feeding issue that needs to be addressed.
If you have diabetes or another risk factor to milk coming around the third day, you may want to consider collecting colostrum prior to birth.
The colostrum and early milk mothers make for their preterm baby are very different from the colostrum and early milk made for a full-term baby. Preterm colostrum has the same disease protection – through antioxidants, antibodies and immunoglobulins (immune factors) – as term colostrum. However, because it has more of these components, it is even more powerful. This superfood reduces inflammation in the gut of a preterm baby and can prevent necrotizing enterocolitis (NEC), which can damage the gut lining in early preterm babies. Preterm babies receiving their own mother’s colostrum have significantly better health outcomes, in the short-term and in the long-term.⁶
First Meals
Colostrum is waiting for your baby at birth. Nursing in the first hour will yield colostrum that is protective and satisfying for your baby. Remember that your baby’s stomach is tiny at birth, see First Few Days of a Breastfed Baby, so a large feeding may look very small! Learning to suck and swallow milk is easier in small amounts.
If for some reason your baby cannot nurse in the early hours, hand express the colostrum so it can be fed to your baby. Hand expressing colostrum almost always yields more volume than using a breast pump in the early days.⁷ Relying on pumping colostrum means you may not have any for your baby because it will all be left stuck to the pump flanges!
The first day, babies usually drink about 30 ml (about an ounce), divided over several feedings. The amount your baby drinks will be increasing each day. On day four, babies usually take 30-60 ml (one to two ounces) per feeding. This volume will slowly increase to about 700 ml (23 ounces) or more per day. Your colostrum will prepare your baby for the larger feeds ahead, and will fill the tiny stomach, as your own milk will be gradually increasing in amount each day. This will gently stretch your baby’s stomach over the first week. By the fourth day, most babies will be drinking colostrum mixed with more mature milk. There is a gradual transition from colostrum to mature milk.⁷,⁸
Colostrum is the most important first food for all infants. Although it is available only in small amounts, it is a powerful superfood!
References:
¹ Marsha Walker, Breastfeeding Management for the Clinician: Using the Evidence, (Jones & Bartlett, 2023),.21, 94, 95.
² Marsha Walker, Breastfeeding Management for the Clinician: Using the Evidence, (Jones & Bartlett, 2023), 21.
³ O Ballard and AL Morrow, “Human milk composition: nutrients and bioactive factors”. Pediatr Clin North Am, 60(1) (Feb 2013): 49-74, doi: 10.1016/j.pcl.2012.10.002. PMID: 23178060; PMCID: PMC3586783.
⁴ Ruth A. Lawrence and Robert M Lawrence. Breastfeeding: A Guide for the Medical Profession (Elsevier. 2022).
⁵ Sy Kim and DY Yi, “Components of Human Breast Milk: From Macronutrient to Microbiome and MicroRNA”, Clinical Experiences in Pediatrics; 63(8) (Aug 2020): 301-309. PMID:32252145;PMCID:PMC7402982. https://pmc.ncbi.nlm.nih.gov/articles/PMC7402982/
⁶ Marsha Walker, Breastfeeding Management for the Clinician: Using the Evidence, (Jones & Bartlett, 2023), 376-377.
⁷ Academy of Breastfeeding Medicine, Clinical Protocol #3: Supplementary Feedings in the Healthy Term Breastfed Neonate, Revised 2017. ABM Clinical Protocol #3: Supplementary Feedings in the Healthy Term Breastfed Neonate, Revised 2017
⁸ Lawrence and Lawrence, Breastfeeding: A Guide for the Medical Professional, (Elsevier. 2022), 100.
Resources:
Maya Bolman, The Basics of Breast Massage and Hand Expression. https://www.mayabolman.com/videos/v/basicsofbreastmassage
Colostro, article from La Leche League Italia “Colostrum”
First Few Days of a Breastfed Baby, published by LLL Asia & Middle East, adapted from Ligue La Leche
Hand Expression
The Power of Hand Expression, article from La Leche League International
ЛЛЛБГ, ЛЛЛ България: Наука за майчиното мляко, article from La Leche League Bulgaria “Breastmilk Science”
Ла Лече Лига Россия: Что такое молозиво?, article from La Leche League Russia “What is colostrum?”
Published May 2026.
*Adapted from La Leche League International information.
