Antenatal expression, also known as colostrum harvesting, is the practice of gently hand expressing or pumping breast milk during the final weeks of pregnancy. This technique allows an expectant parent to collect and store colostrum, the body’s first milk, before the baby’s arrival. Understanding the physiology of milk production and the potential risks involved is important before attempting this practice.
Safety and Medical Considerations
The primary concern with antenatal expression centers on the physiological link between nipple stimulation and uterine activity. Nipple stimulation prompts the release of oxytocin, a hormone known for its role in uterine contractions during labor. Because of this, expressing colostrum carries a theoretical risk of prematurely stimulating the uterus.
For most low-risk pregnancies, starting expression after 36 or 37 weeks is considered safe, but medical clearance is necessary before beginning. It is advised to stop expressing immediately if any painful contractions or uterine cramping occur. Certain high-risk conditions make antenatal expression inadvisable due to the potential for uterine stimulation.
Contraindications include a history of threatened or actual premature labor, multiple pregnancies, cervical incompetence, or any bleeding during the pregnancy. Conditions such as placenta previa or having a cervical suture inserted also mean this practice should be avoided. Discussing individual medical history and pregnancy risks with a midwife or doctor is necessary to ensure safety.
Clarifying the Goal of Antenatal Expression
The core question is whether this practice helps the main milk supply “come in” sooner after birth. The onset of mature milk, known as Lactogenesis II, is a hormonal event primarily triggered by the delivery of the placenta and the subsequent sharp drop in progesterone. Nipple stimulation alone does not significantly accelerate this process.
Colostrum production (Lactogenesis I) begins around the middle of the pregnancy and is already underway when expression starts. Therefore, antenatal expression does not change the timing of the mature milk transition. The true benefit is not accelerating the process but securing a supply of colostrum for the newborn’s immediate needs.
Having a readily available supply of colostrum is beneficial in specific medical scenarios where a baby may need supplementary feeding immediately after birth. This is particularly helpful for mothers with gestational diabetes, as colostrum helps stabilize a newborn’s blood sugar levels. Other situations include a planned elective cesarean section, a known congenital condition like a cleft palate, or anticipated mother-baby separation that might delay initial feeding.
Colostrum is nutrient-dense and packed with immunological factors, making it an ideal supplement that reduces the need to introduce infant formula in the early days. Even small amounts are helpful, and collecting colostrum is best viewed as a preparedness strategy. It provides a valuable resource to support the baby’s health and feeding journey when unexpected challenges arise.
Techniques for Collecting and Storing Colostrum
Once medical clearance is obtained, hand expression is the recommended collection method, particularly in the beginning. Colostrum is produced in very small volumes—often just a few drops—which can easily cling to the parts of a breast pump. Hand expressing allows the parent to collect every drop directly into a sterile container.
Short, frequent sessions are more effective than long ones, with guidelines suggesting expressing for 3 to 5 minutes on each breast, one to three times per day. A sterile syringe, typically 1 milliliter, is the most practical tool for collecting and storing the small amounts of thick, sticky colostrum. Do not be discouraged if only a few drops are collected initially, as this concentrated amount is appropriate for a newborn’s tiny stomach.
For safe storage, collected colostrum must be labeled immediately with the date and time of expression. It can be kept in a freezer for up to six months. The frozen syringes should be placed into a sealed container or zip-lock bag before freezing to maintain hygiene and organization. When going to the hospital, the frozen colostrum should be transported in a small cooler or insulated bag with ice packs.