What Is Colostrum?
Colostrum is the first form of breast milk your mammary glands produce, and it can start as early as 12 to 18 weeks of pregnancy. It's thick, sticky, and runs from deep yellow to orange, which is how it earned the nickname "liquid gold." That rich color comes from concentrated beta-carotene and other nutrients.
Your body makes colostrum for roughly the first two to five days after birth before shifting to mature milk. The amount is small on purpose. A newborn's stomach on day one is about the size of a marble, holding just 5 to 7 mL per feeding. Colostrum's low volume and dense composition line up perfectly with that tiny capacity.
How Colostrum Differs From Mature Milk
Colostrum carries a fundamentally different composition from mature milk. It contains roughly twice the protein, about four times the zinc, and significantly more vitamins A, E, and K. Fat and sugar levels are lower, which makes it easier for an immature digestive system to handle.
The real standout is immune protection. Between 13% and 70% of the total cells in colostrum are white blood cells. It's packed with secretory immunoglobulin A (sIgA), the antibody that coats a baby's gut lining and guards against gastrointestinal infections. Full-term infants can't produce their own IgA for at least 10 days after birth, so this maternal transfer is essential. Colostrum also contains lactoferrin, lysozyme, and epidermal growth factor.
When to Start Harvesting
Most healthcare providers recommend starting at 36 to 37 weeks of pregnancy. Some are comfortable with 37 weeks as the earliest safe starting point. The reason for waiting is that nipple stimulation releases oxytocin, which can theoretically trigger uterine contractions. That said, the landmark DAME trial (Diabetes and Antenatal Milk Expressing), published in The Lancet in 2017, studied 635 women and found that antenatal expressing is safe and does not increase NICU admissions or cause harm to babies.
Begin with one to two sessions per day, keeping each to five to ten minutes (about five minutes per breast). As you get more comfortable, you can gradually build to two to five times daily.
Who Benefits Most From Harvesting
Any pregnant person in a low-risk pregnancy can harvest colostrum, but it's especially valuable for:
- Gestational or pre-existing diabetes: Babies of diabetic mothers face a higher risk of neonatal hypoglycemia. Having colostrum ready at birth can stabilize blood sugar and reduce the need for formula supplementation.
- Planned cesarean section or induction: Milk supply may come in a little later after surgical birth.
- History of low milk supply or previous breastfeeding difficulties.
- Previous breast surgery (reduction, augmentation).
- Babies with expected feeding challenges: Cleft lip or palate, congenital heart conditions, Down syndrome, or intrauterine growth restriction.
- PCOS or other hormonal conditions that may affect early milk production.
- Multiple pregnancies (twins, triplets).
Who Should NOT Harvest
Hold off on colostrum harvesting without provider approval if you have:
- Risk of preterm labor or history of premature delivery
- Cervical insufficiency or cervical cerclage
- Placenta previa
- Unexplained vaginal bleeding
- Preterm premature rupture of membranes
- Pre-eclampsia
Step-by-step: Hand Expression Technique
What you need: Sterile 1 mL or 3 mL syringes with caps (no needles), or a clean spoon and small container. Optional: a warm compress or heating pad.
Preparation:
- Wash your hands thoroughly.
- Find a comfortable, private space and set aside 10 to 30 minutes of uninterrupted time.
- Apply gentle warmth to the breasts if that feels good.
- Massage the breasts, stroking firmly from the top downward toward the nipple to encourage let-down.
Expression:
- Place your thumb above the nipple and first two fingers below, forming a C shape around the areola, about 2 to 3 cm back from the base of the nipple.
- Press the breast tissue backward toward your chest wall.
- Compress by squeezing thumb and fingers together, then roll slightly forward toward the nipple.
- Release and repeat in a rhythmic pattern.
- Rotate your hand position around the areola to access different milk ducts.
- Avoid squeezing or pinching the nipple directly. The technique should feel firm but comfortable.
Collection: Catch drops directly into the tip of a sterile syringe and cap it immediately. You can add to the same syringe throughout a 24-hour period, keeping it refrigerated between sessions. Freeze at the end of each day.
How Much to Expect
Most people collect 0 to 5 mL per session in the early days, often just a few drops. That's completely normal. Total pre-delivery accumulation averages about 40 mL over several weeks of practice. Output tends to climb with consistent practice. Your body keeps producing colostrum throughout late pregnancy, so harvesting does not deplete your supply.
Storage Guidelines
Label each syringe with your name, date, and time.
- Refrigerator (2 to 4 degrees C): Up to 4 to 8 days. Freeze sooner if you won't use it.
- Freezer (-18 degrees C or below): Up to 6 months.
- Thawed colostrum: Use within 12 to 24 hours. Never refreeze.
To thaw, place in the refrigerator or hold under lukewarm running water. Never microwave breast milk or colostrum.
Bringing Colostrum to the Hospital
Transport frozen syringes in a cool bag with ice packs. Keep the ice in a separate bag so nothing leaks onto the syringes. Check your hospital's policy ahead of time: some facilities require the baby's hospital label before storing milk and may not accept colostrum brought at admission.
Benefits for Your Baby
Beyond immune protection, colostrum acts as a natural laxative, helping baby pass meconium (the first stool) more quickly. Meconium contains bilirubin, so faster clearance reduces bilirubin reabsorption and lowers the risk of neonatal jaundice, which affects 60 to 80% of all newborns.
Colostrum also helps establish a healthy gut microbiome in a newborn whose intestines are essentially sterile at birth. It supports the development of the suck-swallow-breathe coordination needed for feeding.
Common Concerns
"Will I use up my colostrum before baby arrives?" No. Your body continuously produces colostrum. The hormonal changes triggered by delivery of the placenta signal the transition to mature milk, independent of any prenatal expression.
"I'm only getting a few drops. Is something wrong?" This is normal. Colostrum is produced in tiny quantities because that's all a newborn needs. Keep practicing.
"Do I need a breast pump?" No. Hand expression is recommended because colostrum is produced in such small amounts that it sticks to pump parts and collection bottles. Syringes capture droplets much more efficiently.
Talk to Your Provider
Bring up colostrum harvesting at a prenatal appointment around 34 to 36 weeks. Your midwife, obstetrician, or lactation consultant can assess whether it's appropriate for your situation and demonstrate the hand-expression technique in person.
This article is for informational purposes only and does not constitute medical advice. Always consult your healthcare provider before beginning colostrum harvesting.