The term “pump and dump” (P&D) refers to the practice of expressing breast milk and discarding it after consuming alcohol, with the goal of making the next feeding safe for the infant. The widespread belief that P&D is necessary to reduce the alcohol content in breast milk is generally a misconception. The act of pumping and discarding milk does not speed up the alcohol clearance process.
Alcohol Transfer into Breast Milk
Alcohol moves from the mother’s bloodstream into the breast milk supply through passive diffusion. The concentration of alcohol in the milk closely mirrors the concentration in the mother’s blood, reaching a state of equilibrium. As the mother’s blood alcohol concentration (BAC) rises, the alcohol level in her milk rises proportionally.
The highest concentration of alcohol in breast milk usually occurs approximately 30 to 60 minutes after a drink is consumed, or up to 90 minutes if consumed with food. Alcohol does not become trapped in the milk; it leaves the milk just as it leaves the blood. The alcohol level in the milk decreases only when the alcohol level in the mother’s blood decreases.
Why Pumping Does Not Clear Alcohol
Pumping and dumping does not clear alcohol from the milk because the body constantly produces milk from the blood. Since the alcohol concentration in the milk is nearly identical to the concentration in the blood, the milk will contain alcohol as long as the mother’s bloodstream does. Pumping only removes the milk present in the breast at that moment.
Discarding that milk does not affect the alcohol circulating in the mother’s system. The liver is the body’s primary mechanism for metabolizing and removing alcohol from the bloodstream, and no external action like pumping can accelerate this process. Alcohol continues to transfer from the blood into newly produced milk until the mother’s blood is clear. Waiting for the body to metabolize the alcohol is the only effective way to ensure the milk is alcohol-free.
Safe Consumption and Wait Times
Planning the timing and quantity of alcohol consumption is the most effective way to minimize infant exposure. A standard drink is defined as 12 ounces of beer (5% alcohol), 5 ounces of wine (12% alcohol), or 1.5 ounces of distilled spirits (40% alcohol). The body metabolizes alcohol at a relatively consistent rate, independent of external factors like drinking water or exercising.
On average, a mother needs to wait approximately 2 to 3 hours per standard drink for the alcohol to clear from her system and her milk. This wait time is an estimate influenced by factors such as the mother’s weight, consumption speed, and whether she ate food.
The best practice is to time consumption immediately after a nursing or pumping session. This scheduling maximizes the window before the next feeding, allowing the body the longest period to metabolize the alcohol. If a feeding is missed due to the wait time, the mother may still need to express milk to relieve engorgement or maintain supply. In this scenario, the pumping is for maternal comfort, and the expressed milk should be discarded.
Risks to the Nursing Infant
While the amount of alcohol transferred to the infant from moderate, occasional consumption is low, higher or chronic exposure carries specific risks. Alcohol can inhibit the milk ejection reflex, temporarily decreasing the amount of milk the baby receives. Studies suggest infants may consume up to 20% less milk in the hours following maternal alcohol consumption.
Alcohol exposure can also disrupt the infant’s sleep patterns, leading to fragmented and shorter periods of sleep. Heavy or frequent maternal consumption can lead to more serious consequences, including reduced motor development, slower growth rates, and signs of sedation such as drowsiness and weakness. The safest option for nursing mothers is to abstain from alcohol consumption.