Pumping and dumping is the practice of expressing breast milk and discarding it instead of feeding it to a baby. This is done to maintain the mother’s milk supply and prevent painful engorgement while avoiding the transfer of potentially unsafe substances to the infant. The milk is discarded because it may contain elevated concentrations of drugs, alcohol, or contaminants that pose a risk to the baby’s health. While rarely necessary, discarding milk becomes a medical necessity under specific circumstances.
Alcohol and the Waiting Game
Alcohol passes freely from the mother’s bloodstream into her breast milk, reaching concentrations similar to her blood alcohol content (BAC). The alcohol level in milk typically peaks about 30 to 60 minutes after consumption, depending on whether it was consumed with food. Pumping and discarding milk immediately after drinking does not accelerate the clearance of alcohol from the milk.
The only way for alcohol to leave the breast milk is for it to metabolize out of the mother’s bloodstream. This process generally takes around two hours for every standard alcoholic drink consumed. For instance, a mother who has two standard drinks should plan to wait at least four hours before nursing or expressing milk for the baby.
Pumping during this waiting period is only necessary if the mother feels uncomfortable or needs to adhere to a regular pumping schedule to protect her milk supply. If milk is expressed while alcohol is still present, that milk must be discarded. The common advice is to wait until the mother feels sober before feeding the baby, as that aligns with the alcohol clearing from the milk.
Medications That Require Milk Disposal
Mandatory milk disposal involves exposure to certain high-risk medications or treatments that are genuinely harmful to the infant. Most medications are compatible with breastfeeding, but a few categories pose a significant risk. Cytotoxic chemotherapy agents, which are designed to kill rapidly dividing cells, typically require the temporary or permanent cessation of breastfeeding.
Radioactive isotopes used in specific diagnostic tests or treatments also often necessitate milk disposal due to the risk of radiation exposure. For example, the isotope Iodine-131 (I-131), used in thyroid treatments, concentrates heavily in breast tissue and milk and usually requires permanent discontinuation of breastfeeding. The radiation from I-131 can pose a serious risk of thyroid damage to the infant.
Other radiopharmaceuticals, such as Technetium-99m (Tc-99m) used in many scans, have a shorter half-life and may only require a temporary interruption of a few hours up to 48 hours. A general rule for waiting after short-term incompatible medication is to wait for five half-lives of the drug, at which point 97% of the substance has been cleared.
A mother taking certain high-dose immunosuppressants, some antimetabolites, or specific anticoagulants may also be advised to discard milk. The use of illegal substances, such as cocaine, heroin, PCP, or high-dose marijuana, requires complete cessation of the substance, not just temporary milk disposal. Consulting specialized resources like the National Institutes of Health’s LactMed database is essential before making any decision about medication.
Common Misconceptions About Illness and Dumping
Many mothers unnecessarily discard milk when they become ill, believing their milk is tainted by the infection. In reality, viral illnesses like the common cold, influenza, and COVID-19 do not require milk disposal. The virus that causes COVID-19, for instance, is not transmitted through breast milk, and the milk contains protective antibodies that can benefit the baby.
Mastitis, a common breast infection, also does not require milk disposal. Continuing to nurse or pump from the affected breast is actually part of the treatment, as it helps to clear the infection and relieve engorgement. Most common over-the-counter (OTC) pain relievers, such as ibuprofen and acetaminophen, are considered safe for use while breastfeeding and do not require milk to be discarded.
Stopping breastfeeding or discarding milk during an illness deprives the baby of valuable protection. Unless a healthcare provider advises otherwise due to a specific medication or a rare condition like a herpes lesion on the breast, the milk remains safe.
Practical Steps for Safe Milk Management
When milk disposal is temporarily required, maintaining the pumping schedule is important for the mother’s comfort and continued milk production. The body relies on regular milk expression to signal the need for ongoing supply, so skipping sessions can quickly diminish output. Pumping at the intervals the baby would normally feed, even if the milk is discarded, helps to prevent painful engorgement and maintain the established supply.
For any substance requiring a waiting period, the clearance time should be calculated using the drug’s half-life or the recommended time until sobriety. If milk is expressed during this questionable period, it should be immediately and clearly labeled with the date and a warning, such as “Do Not Feed,” before disposal. This prevents accidental feeding of the potentially contaminated milk.
A mother should always consult with a healthcare professional, such as a physician or an International Board Certified Lactation Consultant (IBCLC), before deciding to dispose of milk. These experts can check the specific risk using current data and provide personalized advice based on the infant’s age and health.