The human female body is magnificently created for childbearing and feeding a baby. The woman’s breasts are just one part of the awesome human female body. When a mother breastfeeds baby, it is essential for her to know how the breasts work and produce milk to have the best health outcome. Just like any activity, it is best to read information, get instructions and learn what to do, to better the success of your endeavor. Right?
Breastfeeding and milk production go hand-in-hand. By nature’s design for most well, healthy mothers, the more frequently you breastfeed or the more you pump, the breast milk is produced and increases from the stimulation at the breast from baby’s suckling or use of a pump. The period of time at which you start breastfeeding or pumping is the critical factor to milk production. It is essential to breastfeed or pump from the very beginning after delivery, to initiate the lactation process and signal your body to increase milk production. Moreover, breastfeed skin to skin at baby’s cue or demand and at least every 2-3 hours (8-12 times per 24 hours) for as long as baby desires and at least 15 minutes each breast. Make it routine practice during breastfeeding or pumping to do breast massage and compressions for additional stimulation. No matter if delivery is vaginal or cesarean, or if you and baby are separated due to medical problems, you are encouraged to hand express colostrum or begin pumping as soon as possible and within three hours after delivery. The sooner you initiate breastfeeding or pumping after birth, the more quickly your body receives the signals needed to increase milk production, which will result in greater amounts of milk supply over time.
For a better understanding and to learn your essential part in milk production, here’s some basic information about the physiology of the breasts and human milk production. The breast is a remarkable endocrine organ that experiences growth, differentiation, and lactation in response to a complex interplay of hormones and stimulation. During pregnancy, a woman’s changes in hormone levels prepare her breasts to assume the role of nourishing her baby following birth. In mammogenesis stage II, alveolar development, maturation of the epithelium, and proliferation of secretory tissue, increases the volume of breast tissue.
Lactogenesis Stage 1 or secretory initiation takes place during the second half of pregnancy, and is when the breast is first capable of synthesizing unique milk components. Placental lactogen is thought to be responsible. In this stage, small amounts of milk can be secreted by week 16 gestation. By late pregnancy, some women may express colostrum.
Removal of the placenta following delivery causes a rapid drop in levels of placental lactogen, estrogen, and progesterone. This decline in progesterone levels, as well as the presence of elevated levels of prolactin, cortisol, and insulin, initiates lactogenesis stage II.
Lactogenesis stage II is the onset of copious milk secretion between 30 and 72 hours following birth. Usually at days 2 or 3 postpartum, most mothers experience swelling of the breast along with plentiful milk production. Prolactin levels remain elevated for about three months postpartum with a sharp increase of prolactin released with suckling by baby. After the third month, basal prolactin levels fall to normal. Prolactin release occurs only in response to direct stimulation of the nipple and areola from breastfeeding or pumping.
In first time mothers, the secretory activation stage is slightly delayed and early milk volume is lower. Lower milk volume is also observed in mothers who had cesarean births compared to vaginal deliveries. Late onset of milk production has also been seen in mothers who had retained placental fragments, diabetes, and stressful vaginal deliveries. Moreover, other issues of concern that can affect the process of lactation are anything that interrupts the normal development of the breast or interferes with the production of milk, such as breast hypoplasia (insufficient glandular tissue), breast reduction or augmentation. In the postpartum period, some women may experience difficulty with lactation if they have inadequate milk production, poor milk extraction, and insufficient caloric intake to meet demands. Current recommendation for an exclusively breastfeeding mother is to have a minimum excess of 500 calories per day to meet the caloric demands for milk production. However, mother’s body is designed to produce breast milk to feed and protect her baby despite insufficient daily caloric intake. Overall if there are medical problems, each mother’s situation will have to be evaluated and resolutions considered that will lead to best health outcomes for the breastfeeding dyad. Talking to your doctor, healthcare professionals, and a Lactation Consultant about your medical issues and breastfeeding concerns prenatally or soon after delivery, is best to address any issues. Possibly with assistance and support early on, you may be able to reach your breastfeeding goals.
Lactogenesis stage III, previously called galactopoiesis, is the maintenance of lactation. Lactation is maintained by regular removal of milk and stimulation of the nipple, which triggers prolactin release from the anterior pituitary gland and oxytocin from the posterior pituitary gland. For the ongoing synthesis and secretion of milk, the mammary glands must receive hormonal signals. Although prolactin and oxytocin act independently on the cellular level, their combined hormonal action is essential for successful lactation.
Prolactin stimulates mammary gland ductal growth and epithelial cell proliferation and induces milk protein synthesis. Milk production refers to the volume of milk removed from the breast at a feeding or milk expression. Milk production is correlated to the needs of the baby. For example, if a baby’s demand for milk increases, he might feed at the same frequency but increase the amount of milk taken at each breastfeeding. Studies show a baby removes approximately 76 % of the available milk taken at each breastfeeding. Milk synthesis responds to the varying amount of residual milk remaining in the breast after a feeding. Because the breasts are never fully empty of milk, allow your baby to breastfeed on demand whenever he shows hunger cues, even if he just breastfed a short time earlier. Moreover, breastfeeding at night is highly encouraged because prolactin is secreted in a circadian rhythm with major nocturnal hormone elevations. This results in significantly higher prolactin levels at night, especially in the early hours of the morning. In other words, frequent breastfeeding at night combined with the increased prolactin, boosts mother’s milk production and increases supply.
Oxytocin is involved in the milk ejection or letdown reflex. The stimulation of the nipple and areola by baby’s suckling conducts signals to the hypothalamus that trigger release of oxytocin. This results in contraction of the myoepithelial cells, forcing milk into the ducts from the alveolar lumens and out through the nipple. Oxytocin also has a psychological effect, which includes inducing a state of calm and reducing stress. It may also enhance feelings of affection between mother and child, an important factor in bonding.
The storage capacity of breasts varies greatly among women. Storage capacity is related to how the infant’s demand for milk is met by the mother. The size of mother’s breast does not indicate how much milk she may produce. In other words, mothers with small breasts are capable of secreting as much milk over a 24 hour period, as women who have large breasts. A mother with large breasts has more measured storage capacity for milk, but if a mother with small breasts feeds her baby more frequently, despite less storage capacity, she may be able to produce as much milk as the mother with large breasts.
The degree to which the breast is emptied signals the amount of milk to be made for the next feeding. The greater the degree of emptying at a feeding, the greater the rate of milk synthesis after that feed. Milk synthesis is controlled independently in each breast to a considerable degree. Milk also contains a whey protein called the Feedback Inhibitor of Lactation (FIL.) that has strong effects on the mammary secretory cells. FIL concentration increases with longer periods of milk accumulation, downregulating the production of milk. This again reinforces why baby should breastfeed frequently and as long as he desires. When milk accumulates in the breasts because baby is not removing milk frequently, FIL decreases milk production. While not favorable while mother is still breastfeeding, this will help mother wean baby from breastfeeding when she decides to stop later.
A mother’s body, specifically breasts were made to produce milk for feeding her baby. If well and healthy, your body has the capability to increase milk production of its own accord! Start breastfeeding or pumping right after birth. If you have difficulty latching or baby does not nurse, hand express your colostrum every 2-3 hours in the first few days. Do skin to skin time with baby as much as possible, and feed baby on cue/demand and every 2-3 hours (8-12 times per 24 hours) for as long as baby desires. Skin to skin time encourages breastfeeding and enhances milk production. Breast massage or compressions during breastfeeding also enhance milk production. Start pumping every 2-3 hours if baby is too sleepy, not interested in feeding, or suckles poorly. If baby does not nurse and misses a feeding, double pump (pump both breasts) for 15 minutes for breast stimulation and obtain breast milk to feed baby. The stimulation of baby’s suckling during breastfeeding or the alternative stimulation from pumping, triggers the hormones, prolactin and oxytocin to signal the mammary glands for the ongoing synthesis and secretion of milk. Milk removal from the breast by the infant’s suckling is the most important factor to increase milk production. Breastfeeding is an amazing ongoing, milk-producing loop between mother and baby: baby stimulates mom’s nipples/areolas, mom’s breasts produce milk, baby suckles and removes as much milk as he wants, more milk is produced! Together, you and baby can do this! Stay calm and breastfeed on!
REFERENCES
Lawrence R.A., Lawrence R.M. Breastfeeding, A Guide for the Medical Profession, 8th ed. Philadelphia, PA: Elsevier, 2016.
Spencer B., Hetzel Campbell S., Chamberlain K. Interdisciplinary Lactation Care, 2nd ed. Burlington, MA: Jones & Bartlett Learning, 2024.
Walker, M. Core Curriculum for Lactation Consultant Practice. Sudbury, MA: Jones & Bartlett Publishers, 2002.