It is possible for one breast to produce less milk or stop production, a common concern for breastfeeding parents. Milk production is a dynamic process, responding to signals from the body and the baby. While both breasts are designed to produce milk, their output can vary.
The Basics of Milk Production
Breast milk production operates on a “supply and demand” system, where milk removed directly influences amount produced. When a baby suckles, nerve signals are sent to the brain, prompting the release of two hormones: prolactin and oxytocin. Prolactin stimulates the milk-making cells within the breast’s alveoli to produce milk, while oxytocin triggers the “let-down” reflex, pushing milk through the ducts and out of the nipple. While this hormonal response affects both breasts, each breast largely manages its own milk supply based on how frequently and effectively it is emptied.
Reasons for Uneven Breast Milk Supply
Several factors can contribute to one breast producing less milk than the other:
A baby’s preference for one breast, due to a more comfortable latch, a faster milk flow, or physical discomfort when nursing on the other side, such as from an ear infection or torticollis.
If one breast is not emptied as frequently or as thoroughly, milk production on that side will naturally decrease over time due to the supply-and-demand mechanism.
Anatomical differences, as one breast might have more glandular tissue or milk ducts, leading to a higher milk output.
Previous breast surgery (augmentation, reduction) damaging milk ducts or nerves involved in the milk ejection reflex.
Issues like clogged milk ducts or mastitis can temporarily reduce its milk production and may lead to the baby refusing that side due to discomfort or altered milk flow.
Certain medications can also influence milk supply.
Addressing One-Sided Production
If you notice uneven milk production, several strategies can help balance your supply:
Begin each feeding session on the less productive side, as babies often nurse more vigorously at the start of a feed.
Nurse or pump more frequently on the less productive side to increase demand and encourage more milk synthesis.
Ensuring a proper latch on both breasts is important, as an ineffective latch can hinder milk removal and reduce supply.
Applying breast compression during feeds or pumping sessions can help empty the less productive breast more completely.
If your baby consistently refuses one side, pumping that breast regularly.
For personalized guidance, consulting a lactation consultant or healthcare provider is recommended, especially if you experience persistent pain, signs of infection, or significant concerns about your overall milk supply.