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    Collecting and Storing Breast Milk

    Before Pumping  |  Pumping Technique  |  Equipment Cleaning  |  Storage of Human Milk  |  Guidelines for Breast Milk Storage  |  Using Stored Milk  |  Transporting Breast Milk


    Before Pumping

    • Wash your hands.


    • Choose a comfortable, relaxing location.


    • Suggestions to help you relax (which will aid in let-down):

      • Apply warm, moist compresses on your breasts for 3-5 minutes or take a warm shower. If engorged, refer to engorgement instructions.


      • Massage your breasts using the same technique you use for your monthly breast exams.


      • Play calming, relaxing music.


      • Close your eyes and use visualization techniques and deep breathing.


      • Think of your baby or look at baby’s picture, smell something of your baby such as a blanket.

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    Pumping Technique

    • Before choosing a pump, consider the baby’s age and how long you will pump. A lactation consultant can assist you to best meet your needs. An efficient pump is essential to effectively remove milk. If your baby is in the NICU, please ask for the NICU pumping handout.


    • If you are pumping for a one-time feeding or to build up your store of breast milk for returning to work, try pumping in the morning after your baby has nursed, between feedings, or, if your baby has nursed on one breast only, pump the other.


    • If pumping before the mature milk is established, it is best to use a double electric pump.


    • If manual single pumping, pump for 5 minutes on the first breast, 5 minutes on the second, returning to the first for 5 additional minutes, continuing to alternate for a total of 10-15 minutes per breast. An electric double-pump set-up is recommended for long term pumping. If using the double pump set-up, pump for 10-15 minutes to initiate lactation. After the mature milk is in, pump to empty the breasts (up to 30 minutes).


    • Always start on the minimum setting and increase to a pressure that allows you to obtain milk but is not uncomfortable.


    • The "maximum" (on the Lactina pump) or "normal" (on the Classic pump) settings should not be used if it causes discomfort.


    • Remember to stop pumping when the milk is 1 inch from the top of the bottle. Overfilling the bottle could cause milk to be suctioned into the motor of the pump. (If renting a pump, you will be charged a $20 cleaning fee if this happens.)


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    Equipment Cleaning

    • Make sure your equipment is clean before each use. Only wash the cone and collection bottle valve. Use hot, soapy water to wash the cone, rinse it well, dry and store it in a clean location. Cover the cone with a clean towel. You may use a dishwasher or boil pieces for five minutes daily to sterilize. It is not necessary to wash the tubing. Do not get the "air filter" wet as this decreases the amount of suction.

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    Storage of Human Milk

    Put only two to four ounces of milk per container, the amount your baby is likely to take in a single feeding. This avoids waste. Small quantities are also easier to thaw. You can add fresh milk to a container of frozen milk as long as there is less fresh milk than frozen. Cool the fresh milk for 30 minutes in the refrigerator before pouring it on top of the frozen milk in the freezer.

    • Be sure to label every container of milk with the date it was expressed. If the milk will be given to your baby in a day care setting, also put your baby’s name on the label.


    • You can use either hard-sided containers for storing milk or plastic bags. Hard sided containers, either glass or plastic, do the best job of protecting the milk. Plastic milk storage bags, designed for freezing human milk, offer convenience and take up less room in the freezer.

      • The glass or plastic container should have a well-fitting top. Containers should be washed in hot, soapy water, rinsed well, sterilized and allowed to air-dry before use. Leave an inch of space at the top to allow the milk to expand as it freezes.


      • Milk storage bags can be attached directly to a breast pump so that mothers can collect and store milk in the same container. The disposable plastic nurser bags designed for bottle–feeding are less durable and are not designed for long-term storage. Use double bagging to help prevent bursting or tearing. With either kind of bag, squeeze out the air at the top before sealing and allow about an inch for the milk to expand when frozen. Stand the bags in another larger container on the refrigerator shelf or in the freezer.

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    Guidelines for Breast Milk Storage

    • Room temperature (66-72°F or 19-22°C) - up to 6 hours


    • In refrigerator (32-39°F or 0-4°C) - up to 6 days


    • In freezer compartment inside refrigerator (temperature varies) - up to 2 weeks


    • In freezer compartment with a separate door (temperature varies) - up to 3-4 months


    • In a separate deep freezer (0°F or -19°C) - up to 6 months or longer


    • Consult with a lactation consultant if the baby is in NICU or has special needs.


    • Milk must be frozen within 48 hours of pumping.


    • Fresh milk that has been cooled first in the refrigerator may be added to already frozen milk.


    • Previously frozen milk that has been thawed can be kept in the refrigerator for up to 24 hours.


    • To prevent spoilage, do not store expressed milk on the door of a refrigerator or freezer.

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    Using Stored Milk

    • Human milk should be thawed and heated with care. Warm or defrost milk in a container of warm water or under cool running water, gradually increasing the temperature of the water to heat milk to feeding temperature. This is preferable to warming over the stove. Do not warm milk in the microwave – there has been some evidence of alteration of immunologic factors by microwaves, as well as uneven heating which could be dangerous for baby.


    • Milk that has been offered to the baby and not taken may be offered one more time within the next four hours provided it is refrigerated between feedings. The milk should be discarded if not taken again.


    • Do not refreeze breast milk.


    • Human milk may separate into a milk layer and a cream layer when it is cooled. This is normal. Shake it gently to redistribute the cream before giving it to the baby.


    • Discard any milk that smells or tastes sour.

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    Transporting Breast Milk

    • If you are transporting milk, use an ice cooler with ice or frozen packs.

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