Storing Breast Milk
Storing breast milk is easy. Begin with clean hands and wash pump parts and bottles according to manufacturer's directions. Pumped milk is safe at room temperature (about 78°F) for up to four hours in a clean container. Coolers that are well chilled with ice packs are dependable for about 15 hours. Milk can be safely stored in a refrigerator for up to five days, and in a freezer for two to three months. A deep freeze (that keeps ice cream frozen solid) can preserve pumped milk for six months or more.
Moms need to remember to investigate whether there will be a refrigerator available to them at work. Many businesses have policies that support breastfeeding moms. They may provide a pumping room with a sink, rental grade pump, and a refrigerator, or they may allow milk to be stored in a nurse's station. Often mothers must provide their own coolers, which are important for transporting milk home. Once milk has been chilled, it should be kept at a constant temperature to preserve freshness.
Most moms begin storing extra milk in the freezer during maternity leave. They choose a time to express milk each day when they are rested and their breasts feel full. For many women this is in the morning, although some moms like to pump for a short while in the middle of the night. In this instance, they nurse the baby on one breast, as if he or she were a twin, and then pump the other breast for about 10 minutes.
Milk freezes best in glass or hard-plastic containers, or in plastic bags manufactured specifically for breast milk storage. (Soft-plastic bags can easily split when frozen, and sometimes leach a plastic taste into the milk.) It is a good idea to stash enough milk to cover the baby's feedings on the first day back at work, along with a small emergency reserve. Once moms are back at work they no longer need to freeze milk. From that point on, the milk that is pumped one day is fed to the baby the next. Friday's milk is stored in the refrigerator until Monday. Frozen milk can be thawed overnight in the refrigerator, or it can be quickly thawed by placing the frozen container in a bowl of hot water. Microwaving human milk is discouraged because it creates a scalding risk, and encourages bacterial growth. Sometimes thawed milk looks "soapy" because freezing alters the fat cells. Warming the milk and gently shaking it can help mix it back together. The milk is still good and the baby generally doesn't mind.
Once thawed, milk should not be re-frozen. If the baby doesn't finish all the milk in a bottle at a feeding, it can go back into the refrigerator for a short while—an hour or two, but should be discarded if not consumed by then.
To prevent waste, most moms learn to store milk in individual serving sizes. A baby younger than 2 months of age probably needs 2 to 3 ounces at a feeding. Babies from 2 to 4 months of age typically will be happy with 3 to 4 ounces of milk at a feeding. Older babies may want 4 to 6 ounces at a feed. Since babies can get thirsty between meals, moms can leave a few 1-ounce bottles with the sitter each day to cover thirst needs and snacks, or to be offered if the baby seems hungry shortly before mom is due to arrive. If mom's breasts are full, it can be uncomfortable for her if the baby isn't interested in nursing for several hours.
Most babies begin solid foods around 4 to 6 months of age. After this point, their dependence on mother's milk is less intense, and the whole process begins to feel more relaxed. The sitter can use some pumped milk to mix the baby's cereal or it can be added to fruit. After the first six months, many women begin to decrease their pumping frequency.Some adjust to going all day without pumping and just nurse when they are with their baby.