Antenatal milk expression, often called colostrum harvesting, is the practice of gently hand-expressing colostrum, the earliest form of breast milk, during the final weeks of pregnancy. Colostrum is a nutrient-dense, antibody-rich fluid produced by the breasts starting around the sixteenth week of gestation. Collecting this allows a parent to build a small reserve before the baby arrives. This reserve can be invaluable if the newborn requires immediate supplementation after birth, supporting newborn health outcomes when undertaken with appropriate timing and safety considerations.
Recommended Timing for Antenatal Expression
The most commonly advised time to begin antenatal expression is after reaching 36 to 37 weeks of gestation in an uncomplicated pregnancy. This timing is a medical precaution, aligning with the period when the pregnancy is considered full-term or near-term. Starting at this stage minimizes the theoretical risk of stimulating uterine activity, which could potentially trigger labor.
Obtaining clearance from a healthcare provider is mandatory before beginning this practice. Your doctor or midwife needs to review your medical history to ensure there are no specific risks unique to your pregnancy. Once cleared, a person typically begins with short, gentle sessions lasting only a few minutes once or twice a day. The focus is on establishing the technique and collecting small droplets, not on collecting large volumes.
Medical Reasons for Colostrum Harvesting
While many parents choose to harvest colostrum, the practice is recommended for those with specific maternal or infant health factors. A common indication is a diagnosis of gestational or pre-existing diabetes. Infants born to parents with diabetes are at an increased risk of experiencing low blood sugar levels immediately following birth.
Having a supply of colostrum allows medical staff to provide the baby with human milk to stabilize blood glucose levels, potentially avoiding formula supplementation. Harvesting is also recommended if an infant is anticipated to be separated from the parent, such as in cases of expected admission to the Neonatal Intensive Care Unit (NICU). Stored colostrum ensures the baby receives its parent’s milk when regular feeding may be difficult.
Other circumstances that make harvesting beneficial include an anticipated challenge with infant feeding, such as a known diagnosis of cleft lip or palate. Certain maternal conditions can also correlate with delayed milk supply establishment. These include a history of breast surgery, polycystic ovary syndrome, or taking specific high blood pressure medications like beta-blockers. Having a reserve of colostrum provides nutritional and immunological support during this transitional period.
Safety Concerns and When to Avoid Pumping
The primary safety concern involves the potential for stimulating uterine contractions. Nipple stimulation, a necessary part of the expression process, causes the release of oxytocin. Oxytocin is the hormone responsible for the milk ejection reflex, but it also stimulates uterine contractions.
Although the amount of oxytocin released through gentle hand expression is usually insufficient to initiate labor in a low-risk pregnancy, the risk increases for those with complications. Therefore, antenatal expression is strictly advised against in several high-risk scenarios. Contraindications include a history of threatened or actual preterm labor in the current or previous pregnancies.
The practice should also be avoided by anyone diagnosed with placenta previa, a condition where the placenta partially or totally covers the cervix. Other serious conditions that prohibit harvesting include preeclampsia, a short cervix, or the presence of a cervical suture. If an individual feels any uterine cramping or contractions during an expression session, they must stop immediately and notify their healthcare provider.
Techniques for Expression and Storage
Hand expression is the preferred method for colostrum harvesting before birth, rather than using a mechanical pump. Colostrum is produced in very small volumes, often just a few drops at a time. Its sticky consistency makes it difficult to collect with a pump, as the milk can adhere to the pump flanges and tubing. Hand expression allows for a more targeted and gentle collection of these small droplets.
To begin, a person should wash their hands and gently massage the breast to encourage flow. They then use a “C” shape with their fingers, placing the thumb and forefinger about two to three centimeters back from the nipple. Gently compress and roll the fingers toward the nipple. The collected droplets of colostrum should be drawn up directly into a small, sterile syringe, typically 1 milliliter in size.
Each syringe must be clearly labeled with the person’s name, the date, and the time of expression. Once collected, the syringe should be placed immediately in the freezer for long-term storage. When going to the hospital for the birth, the frozen syringes should be transported in an insulated bag with a freezer brick. This maintains the cold chain until they can be transferred to the hospital freezer.