Antenatal milk expression, also known as colostrum harvesting, is the process where expectant mothers gently hand-express and collect their first milk before the baby’s birth. Colostrum is a thick, nutrient-dense fluid produced by the breasts starting around the 16th to 20th week of pregnancy. This practice allows a mother to store this highly protective early milk for use if the newborn requires supplementation after delivery. While the technique offers several benefits, it must only be initiated after receiving clearance from a healthcare provider.
Medical Clearance and Safe Timing
Consultation with an obstetrician or midwife is mandatory before beginning any form of antenatal milk expression. The primary concern is that nipple stimulation triggers the release of oxytocin, a hormone that can cause uterine contractions. Although there is little evidence that daily hand expression in low-risk pregnancies can induce labor, medical guidance is necessary to ensure safety.
For mothers with low-risk pregnancies, the recommended window to begin expression is usually after 36 or 37 completed weeks of gestation. Starting the process too early can pose a risk of preterm labor. If any persistent uterine contractions or vaginal bleeding occur, stop expressing immediately and contact a healthcare provider.
Antenatal expression is not advised for all pregnant individuals. Contraindications include a history of threatened or actual premature labor in the current or previous pregnancies. The practice should also be avoided in cases of placenta previa, cervical incompetence, or a multiple pregnancy without explicit medical approval.
Why Harvest Colostrum Before Delivery
Antenatal colostrum harvesting is often recommended when a baby is anticipated to have difficulty feeding or maintaining stable blood sugar levels after birth. Babies born to mothers with gestational or pre-existing diabetes are at an increased risk of neonatal hypoglycemia. A stored supply of colostrum helps stabilize the baby’s blood sugar without requiring formula or an intravenous dextrose infusion.
Stored colostrum is also beneficial when mother and baby separation is expected, such as after a planned Caesarean section or if the newborn requires neonatal intensive care. Colostrum is packed with antibodies and protective substances that support immunity and is easily digestible. Providing this early milk minimizes the chance of needing formula supplementation, which is important for babies facing feeding challenges like cleft lip or palate.
Expressing colostrum before birth also allows the mother to learn and practice hand expression. This skill can be useful later for managing engorgement or stimulating milk supply, increasing confidence in breastfeeding. Furthermore, the high energy content of colostrum helps the baby pass meconium, the first sticky stool, reducing the risk of jaundice.
Techniques for Harvesting and Safe Storage
Hand expression is the preferred method for colostrum harvesting over using a breast pump. Colostrum is produced in very small, concentrated volumes, often just a few drops or milliliters at a time, making it difficult for a pump to collect efficiently. Hand expression allows the mother to collect the thick, sticky fluid directly into a sterile container or syringe.
To begin, a mother should wash her hands and find a comfortable, relaxed position, often after a warm shower to encourage milk flow. She should use a C-shape hand position, placing her thumb above the nipple and fingers below it, a few centimeters back from the areola. The technique involves gently pressing straight back toward the chest wall, then compressing the thumb and fingers together without sliding them over the skin, and finally releasing.
This compress-and-release motion is repeated rhythmically in the same spot for a few minutes, rotating the hand position around the areola to access different milk ducts. The small droplets of colostrum should be collected immediately, ideally by drawing them directly into a sterile, cap-tipped syringe. Mothers can express on each breast for about five to ten minutes per session, aiming for two to three sessions in a 24-hour period.
Storage Guidelines
For storage, colostrum can be collected over the course of one day in the same labeled syringe, keeping it refrigerated in between expressions. Fresh colostrum can be stored in the refrigerator at 4°C or lower for up to 72 hours.
For longer preservation, the syringe should be placed inside a sealed, labeled plastic bag and transferred to a freezer as soon as possible after the final collection for the day. Colostrum can be stored in a deep freezer for six to twelve months, or for about three months in a freezer compartment with a separate door. When transporting the frozen supply to the hospital, it must be kept in an insulated cool bag with ice packs. Once thawed, the colostrum should be used within 24 hours.