Your body starts producing colostrum on its own during pregnancy, typically between weeks 12 and 16 of gestation. You don’t need to do anything special to trigger this process. The real question most people have is whether they can collect it before birth and how to support a strong supply once the baby arrives.
When Your Body Starts Making Colostrum
Colostrum production begins in the second trimester through a process called lactogenesis I. The milk-producing cells in your breasts begin secreting this thick, yellowish fluid as early as 12 weeks into pregnancy. By the third trimester, some people notice small amounts leaking from their nipples, while others never see any leaking at all. Both are completely normal and say nothing about your future milk supply.
The hormonal setup during pregnancy is interesting. Prolactin, the primary milk-making hormone, rises steadily throughout pregnancy and stimulates your breast tissue to grow and prepare for production. But high levels of progesterone and estrogen actually block prolactin from triggering full milk secretion. This is why you produce only small amounts of colostrum rather than a full milk supply while pregnant. After you deliver the placenta, progesterone and estrogen drop sharply, removing that block and allowing prolactin to ramp up production.
Why Colostrum Matters for Your Baby
Colostrum is concentrated nutrition packed into very small volumes. It contains about 14 to 16 grams of protein per liter, nearly double the protein concentration of mature breast milk. It’s low in fat but rich in immune-protective compounds, particularly IgA (an antibody that coats your baby’s intestinal lining and blocks bacteria) and lactoferrin (a protein that inhibits the growth of harmful bacteria). Think of it as a highly concentrated first vaccine and meal rolled into one.
The volumes are tiny by design. On day one, a typical feeding delivers around 5 milliliters of colostrum. By day three, that increases to roughly 20 to 25 milliliters per feed. A newborn’s stomach is only about the size of a marble at birth, so these small amounts are exactly what your baby needs.
Hand Expression Before Birth
Antenatal colostrum expression, or hand-expressing colostrum during late pregnancy, has gained popularity. Some people choose to collect and freeze small amounts so they have a backup supply ready after delivery. This can be particularly useful if you’re expecting a baby who may have difficulty feeding right away, such as babies with certain heart conditions or cleft palates, or if you have diabetes and your baby may need extra help stabilizing blood sugar.
If your care provider gives you the green light, here’s how it works:
- Wash your hands before every session.
- Warm up first. A warm compress on your breasts or a warm shower helps get things flowing.
- Use the C-hold. Place your thumb above the nipple and your fingers below, forming a C shape around the areola.
- Press, compress, release. Push back toward your chest wall, gently squeeze your thumb and fingers together, then release. Repeat in a steady rhythm.
- Rotate around the areola. Move your fingers to different positions to access all the milk ducts.
- Express from each breast twice per session, up to two or three sessions per day.
The amounts will be very small, sometimes just a few drops. A clean plastic spoon works well for collecting, and you can transfer the colostrum into small 1 or 2 mL syringes. Store filled syringes in the freezer, or keep them in the fridge until the end of the day before freezing.
Risks of Expressing Too Early or Too Aggressively
Antenatal expression is not risk-free, and international experts recommend it only in individualized, clinician-guided situations rather than as something every pregnant person should do. Unsupervised or aggressive expression has been linked to prenatal mastitis (a painful breast infection), anxiety about supply, and in clinical observations, early-term births around 37 weeks.
There are risks for the baby too. If parents rely heavily on pre-expressed colostrum after birth, it can lead to overfeeding, decreased interest in latching at the breast, and poor latch development. Once the stored colostrum runs out, some families end up turning to formula earlier than planned. The pressure to stockpile large quantities, sometimes fueled by social media advice, can do more harm than good. If you’re considering antenatal expression, talk to your midwife or lactation consultant first so you have guidance tailored to your pregnancy.
Supporting Colostrum Production After Birth
The single most effective thing you can do to support colostrum production after delivery is to put your baby to the breast early and often. Frequent nursing in the first hours and days stimulates prolactin release and signals your body to keep producing. Aiming for 8 to 12 feeds in 24 hours during the newborn period sets the foundation for your supply.
Skin-to-skin contact also plays an important role. Holding your baby against your bare chest helps regulate their temperature and breathing, and expressing milk during or right after skin-to-skin time has been associated with greater milk production. Research on preterm infants found that this effect was most measurable for mature milk production in later weeks rather than for colostrum itself, but early skin-to-skin still supports breastfeeding initiation, earlier latching, and better feeding tolerance.
If your baby can’t latch right away, hand expression within the first hour after birth can help. The same C-hold technique described above works for postpartum expression. Even collecting tiny amounts of colostrum by hand and feeding them to your baby with a spoon or syringe keeps the supply signals going while you work on latching.
What Normal Colostrum Looks Like
Colostrum is thick and sticky, noticeably different from the thinner, whiter mature milk that comes in around days 3 to 5. The color is usually yellowish, sometimes ranging from clear to deep gold or even slightly orange. Foods with strong pigments, certain medications, and natural variation can all affect the shade. None of these color differences indicate a problem with quality. If you notice colostrum on your bra or clothing during pregnancy, that’s simply your body doing what it’s designed to do.