Breast-feeding offers infants the healthiest nutritional start. Sometimes in today’s busy life, mothers have to spend time away from their infants, so pumping and storing breast milk becomes necessary.
Mothers pumping — or expressing — milk for an infant have a number of choices for storing and preserving it.
The guidelines that follow are based upon information supplied by Anne Merewood, director of lactation services at the Breastfeeding Center of Boston Medical Center, and were published in Contemporary Pediatrics.
The guidelines concern only healthy babies. If your infant has special problems, consult your pediatrician.
Freshly expressed or pumped milk placed in a refrigerator set at 39 degrees will remain usable for 72 hours.
Milk expressed or pumped at work and placed in a cooler along with some re-freezable ice and kept at 59 degrees will remain usable for 24 hours.
At room temperature, which is 77 degrees, the milk will last only about four hours.
If you pump your breasts away from home, store the milk in a cooler with re-freezable ice and refrigerate it upon your return, you can be sure that your infant will have a healthy supply of breast milk when you are at work or otherwise away.
Breast milk can be preserved for longer periods by freezing it in a container with an airtight lid. This allows you to save a supply for short-term emergencies.
The freezer area inside your refrigerator — limited mostly to small or older refrigerators — will keep milk for up to two weeks depending on the conditions of the freezer.
The conventional freezer with a separate door outside the refrigerator will preserve milk for three to six months — the back is colder than the part near the door — and an independent, manually defrosted unit will preserve milk for 6 to 12 months.
If your freezer keeps ice cream firm, it will do a good job. Remember that thawed breast milk should not be refrozen.
Brand name bottle liners are sold specifically for storing breast milk, but generic bottle liners on a tear-off roll are much less expensive and do the job. You can find these at your pharmacy.
Freeze milk in small amounts of about 2 to 4 ounces. Small amounts are easier to thaw and less wasteful if your baby is not hungry enough to empty the liner.
Leave space at the top for the liquid to expand when frozen and double bag to protect against tears. Write the amount and the date on freezer tape and affix it to the outer liner.
If it is for use at a day care, add the baby’s name to the tape. Then, slip several filled liners into a heavier resealable zipper-type bag.
Do not thaw milk in the microwave. Doing so will destroy much of the immunologic benefit.
To thaw breast milk, move it to the refrigerator the day before, leave it at room temperature, place it in lukewarm water or place it under warm running water.
Fat naturally separates and rises in the bottle after thawing. Gently tip the bottle back and forth to distribute it throughout the bottle.
A mother’s diet might affect the color or odor of the milk, but Merewood said there is general agreement that if proper precautions have been taken in handling and storing, the milk can be used as long as the baby doesn’t reject it.
Sally Robinson is a clinical professor of pediatrics at UTMB Children’s Hospital, and Keith Bly is an associate professor of pediatrics and director of the UTMB Pediatric Urgent Care Clinics. This column isn’t intended to replace the advice of your child’s physician.