Colostrum is a complete food for newborn babies.

Colostrum is the earliest breastmilk produced, beginning in mid-pregnancy (12-18 weeks) and is continually produced for the first few days after baby’s birth. It is a thick, sticky, concentrated milk and is usually yellow, clear, or white, although it could be other colors as well. It is made up of immune factors, protein, sugar, and fats.

From the American Academy of Pediatrics: “Colostrum provides all the nutrients and fluid that your newborn needs in the early days, as well as many substances to protect your baby against infections. Its color and thickness are due to the fact that it is higher in these protective factors. (Compared with more mature human milk, colostrum is also higher in protein, slightly lower in sugar, and significantly lower in fat.) While your breasts will not feel full the day that you give birth, you already have enough colostrum to nourish your baby. Your body will produce colostrum for several days after delivery until your milk increases in amount and becomes more creamy or white in color—a time that mothers frequently refer to as the milk ‘coming in’.”

Why is colostrum important? 

Colostrum is the most important first food for all infants. Although it available only in small amounts, it is a powerful food! Colostrum gives your baby immunity to the germs that are in the surrounding environment. It is protective, coating the intestines to fence these germs out so they cannot be absorbed into your baby’s system. This barrier seals your baby’s insides, preparing your little one for a healthy life. Colostrum also kills harmful microorganisms and provides protection from inflammation. It is a laxative as well, and will help clear your baby’s system of the meconium (black stool) that has built up while baby was inside of you. Early clearing of meconium helps to reduce jaundice. In healthy full-term babies, colostrum helps to prevent low blood sugar. Colostrum is important for all babies, and it is particularly important to preterm, immature babies. Premature babies receiving colostrum have significantly better health outcomes.

Your baby’s first meal

Colostrum is waiting for your baby at birth. When you nurse in the first hour after birth, your baby gets a big serving of colostrum which both protects them and nourishes them. Remember that your baby’s stomach capacity is very small at birth, so a large feeding to them may seem very small to you. Learning to suck and swallow milk is easier in small amounts. If for some reason your baby cannot nurse in the early hours, you can hand express the colostrum so that it can be fed to your baby. You can generally get more colostrum through hand expression than by using a breast pump, especially in the first day or two.

In the first 24 hours, most babies drink about an ounce, divided over several feedings. Your colostrum will prepare your baby for the larger feeds ahead, and will fill their tiny stomach. 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 as your body shifts production. There will still be some colostrum in your milk for the first few weeks.

Collecting colostrum while pregnant 

Your body begins to make colostrum in the first trimester of pregnancy.

Sometimes colostrum ‘leaks’ onto the person’s bra or other clothing; others do not experience any outward signs that the breasts are preparing for lactation even as the pregnancy progresses. The fluid could be thin or thick, and is usually yellow-ish because of beta-carotene, one of the protective components of milk. At the time of the baby’s birth, more colostrum is being produced by the breasts than the baby will need. However, some fear that the baby “won’t get enough” or that the “milk won’t come in,” and want to express colostrum before the baby is born. According to research, the breasts make 10-100 ml of colostrum per day, averaging about 30 ml or an ounce per day–more than the baby needs.

Why do people express and store colostrum before birth? 

  • Some people want to practice hand-expression of milk for after the baby is born. Colostrum is thicker and made in smaller volume than later milk, but the technique for collecting milk through hand expression is the same.
  • Some families are worried about  a delay in transitioning to mature milk. For example, if you have diabetes, a planned c-section, or some other complication, the onset of full milk production may be a day or so later. In this case, having stored colostrum may be helpful.
  • You anticipate a baby being unable to latch after birth due to a medical problem including a cleft palate.
  • Some parents feel better expressing before birth because it increases their confidence knowing that their breasts are preparing to make milk.

Is prenatal colostrum collection safe?

Some parents worry that milk expression will trigger premature labor contractions. Prenatal expression of colostrum has not been shown to trigger labor contractions if the pregnancy is otherwise stable. (Read the study here). In fact, nipple stimulation is not especially effective in starting or enhancing labor contractions.

How to store colostrum

  • Use small, food-safe storage containers with secure lids. Newborns will only need less than one ounce per feed, so don’t use large containers.
  • Label the container with the date and time of when you expressed.
  • Freeze the colostrum soon after expression.
  • You can add more small amounts of colostrum to the frozen container, but not enough that would thaw the stored colostrum.
  • Thaw under running warm water, not in a microwave oven. Use the thawed colostrum within 24 hours. 

Alternatively, some families choose to store colostrum in syringes which are ready to feed to baby. You can place the syringe into a zip-lock bag before putting it into the freezer.



Engorgement, LLL USA

Is My Baby Getting Enough Milk, LLL USA

Storing Human Milk, LLL USA

Set Yourself Up for Breastfeeding Success after Cesarean Section, LLL USA blog

Colostrum: Prenatal /Antenatal Expression, LLLI

Hand Expressing, LLLI

The Power of Hand Expression, LLLI


My Birth Story: Coco’s Early Arrival, LLL USA blog

Diary of an Expectant Mother, LLL USA blog



Please contact a local LLL Leader with your specific questions.

Medical questions and legal questions should be directed to appropriate health care and legal professionals.


Page updated March 2020

Resource adapted from LLLI materials.