Antenatal expression, often called colostrum harvesting, involves gently extracting early breast milk before delivery. At 39 weeks, a person is considered full-term, a common time to consider this preparation. The decision to begin expression balances the benefits of having a stored milk supply with the physiological response the action can trigger. This article explores safety considerations, the nutritional value of the collected milk, and practical steps for beginning expression.
Understanding the Risk of Uterine Contractions
The primary concern with antenatal expression is stimulating uterine contractions that could initiate labor. Nipple stimulation, whether by hand expression or pumping, triggers the release of oxytocin. Oxytocin is the hormone responsible for causing the uterus to contract during labor and for the milk ejection reflex after birth.
Because of oxytocin’s role, medical professionals advise waiting until at least 37 weeks of gestation before beginning expression. Even at 39 weeks, clearance from a healthcare provider is mandatory before starting. A provider must confirm a low-risk pregnancy status to ensure the stimulation does not pose a risk of precipitous labor.
Specific pregnancy complications are contraindications where antenatal expression must be avoided entirely. These include a history of threatened or actual premature labor in current or previous pregnancies. Other absolute contraindications are placenta previa, a shortened cervix, a cervical cerclage (stitch), or unexplained vaginal bleeding. For a healthy, low-risk, full-term pregnancy, the risk of expression causing labor is low, but the potential for heightened uterine activity necessitates medical guidance.
Primary Goal: Colostrum Harvesting
The substance collected during antenatal expression is colostrum, the thick, yellowish fluid often called “liquid gold.” This first milk is produced from around the 16th week of pregnancy and is distinctly different from mature breast milk. Colostrum is highly concentrated and packed with specialized components suited for the newborn’s first few days of life.
Colostrum is particularly rich in immunoglobulins, a type of antibody that provides passive immunity and protects the baby from various infections. It also acts as a gentle laxative, helping the newborn pass meconium (the first sticky stool), which aids in preventing jaundice. Furthermore, it contains a high concentration of protein and fat, and is easy for a newborn to digest.
Having a stored supply of colostrum can be beneficial if the newborn has difficulty latching or requires supplementation for medical reasons. This stored supply ensures the baby receives human milk instead of formula, especially if there is a temporary delay in the mother’s mature milk coming in. This reserve is useful if the baby is at risk for hypoglycemia (low blood sugar), as colostrum helps stabilize blood glucose levels.
Practical Guide to Antenatal Expression
When beginning antenatal collection, manual hand expression is often recommended over using an electric pump. Colostrum is produced in very small, droplet amounts, and hand expression allows for precise collection, preventing the small volume from being lost in pump parts. Hand expression is also generally more comfortable and less aggressive on the breast tissue.
A common starting regimen involves expressing for a few minutes, two to three times per day. Begin with sessions lasting about five minutes on each breast, building up the duration slowly as tolerated. The collected droplets should be drawn up directly into sterile, small-volume syringes, typically 1 milliliter in size, for hygienic storage.
Once the syringe is filled, label it with the date and time of expression before immediately placing it in a freezer. Frozen colostrum can be stored for up to six months. When transporting to the hospital, the frozen syringes should be placed in a small, insulated cool bag with an ice pack to maintain the temperature until they can be transferred to the hospital freezer.
Conditions Where Pre-Birth Pumping is Recommended
While many people express colostrum for general preparedness, certain maternal or fetal conditions make antenatal expression a medically advised strategy. The most common indication is for individuals with pre-existing or gestational diabetes. Babies born to diabetic mothers are at increased risk for neonatal hypoglycemia, and having colostrum ready can rapidly correct low blood sugar without formula supplementation.
Expression is also recommended if a delayed start to feeding is anticipated, such as with a planned Cesarean section or if the baby is expected to require a stay in the neonatal unit. For babies diagnosed with conditions like a cleft lip or palate, where immediate effective latching may be difficult, a colostrum reserve ensures they receive crucial nutrients and antibodies. Mothers with specific anatomical challenges, such as breast hypoplasia or a history of significant breast surgery, may be advised to express to gauge and stimulate milk production.