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Expert Answers To Your Top Questions About Pumping, Storing And Reheating Breast Milk

Breastfeeding isn’t without its bumps in the road. Our experts are here to help you navigate.

How do you warm up breast milk?
Breast milk can be warmed in a cup of warm water or in a bottle warmer, or in a refrigerator if it was frozen. Never thaw frozen breast milk at room temperature and never microwave breast milk, as it can change the milk’s nutritional and bacterial makeup. Test the milk on your inner wrist before feeding to baby to make sure it’s at room temperature. If you’re out and about with no way to warm the milk, you can try giving baby the cold milk—many babies do just fine when it’s the only option.

If I’m also pumping, should I still feed baby from both breasts during every feeding?
It’s always a good idea to offer baby both breasts at each feeding, letting baby finish on the first side before offering the second breast. Baby may or may not want to eat on the second side, which is fine either way. If baby decides he or she isn’t interested in the second side, it’s not necessary to pump the unused side—just make sure to start the next feeding on that side. When you’re pumping throughout the day to store extra milk or to increase your milk supply, you should always allow baby’s hunger cues to determine when to feed baby and not let pumping interfere with or limit baby’s feedings.

Can I freeze breast milk after it's been sitting in the fridge for a couple days?
Absolutely. Refrigerated breast milk is good for up to one week and can be placed in the freezer at any time before it expires, ideally within the first 72 hours. If you know ahead of time you aren’t going to use the milk within a week, it’s best to place it in the freezer immediately. Always label the storage bag with the date the milk was expressed and the number of ounces prior to freezing. Make sure to store milk in the back of the refrigerator, where it’s coldest, and avoid storing breast milk in the refrigerator door.

If I don’t pump enough milk to fill up a storage bag, can I add more milk later on before freezing?
It’s perfectly safe to combine milk into one storage bag prior to freezing, but you’ll want to avoid adding warm milk to previously chilled milk (since this can also affect the nutritional makeup), so make sure to cool the new milk before combining. It’s also okay to combine milk from different days and use the date of the first milk expressed when labeling.

Expert: Stephanie Nguyen is a Registered Nurse, Women's Health Nurse Practitioner and International Board Certified Lactation Consultant. She is also the founder of Modern Milk, a contemporary mom and baby facility in Scottsdale, Arizona.

I'm a new mom and strictly breastfeeding. What can I do about the pain from being too full?
Many women feel this engorgement, especially the first week or two after giving birth. The combination of breast milk, increased blood flow and swelling can make your breasts feel extremely heavy and hard. Your new breast milk is a very different consistency and volume than the thick, yellow colostrum your body was producing before, and adjusting takes some time. If you’re feeling engorged, it's important to feed, pump or hand express your milk to prevent pain and possible mastitis, an inflammation of the breast usually caused by clogged milk ducts.

How often should I pump?
Unfortunately there is no right answer to this—it really depends on baby, your schedule and your needs. If you're breastfeeding exclusively, that could mean feedings every two to three hours or more frequently if a growth spurt is coming up—and obviously you'll want to have enough milk for those feedings before you stock away extra. You can try pumping 30 to 60 minutes or more after breastfeeding, but ultimately you'll have to experiment to find the pattern that works best for you.

Breastfeeding is killing my nipples! How can I ease the pain?
Nipple pain is a common complaint for breastfeeding moms, and a less-than-perfect latch is the most likely culprit. Other things that may contribute to nipple soreness: bras that are too tight and removing baby from your breast without breaking the suction first. If baby is latched on and sucking, and you need to end the feeding, the best way to break the suction is either by gently pressing down on your breast near baby's mouth, or inserting a clean finger into the corner of baby's mouth. Also, soreness can stem from chapped nipples. To avoid chafing, blot your nipples dry after feeding and apply an emollient, like HPA Lanolin, if your doctor okays it. If nipple soreness doesn't clear up, contact your doctor or a lactation consultant for more helpb.

Expert: Katie Lynch is a Certified Lactation Counselor, a Certified Childbirth Educator and a Registered Nurse who specializes in Labor and Delivery and Reproductive Medicine.

Is it okay to give baby formula at night and breast milk during the day?
Many moms breastfeed as well as supplement with either expressed breast milk or formula, especially as baby gets older. Breastfeeding doesn’t have to be an all or nothing decision. Formula can be introduced during the night or even feeds during the day, depending on baby’s needs and your schedule or circumstance. Know that once breastfeeding is established, many moms who want or need to give up a feed or two can continue to produce adequate milk supply for an extended period of time. The key is consistency. Formula is an alternative that provides adequate nutrition for baby’s growth and development, and by continuing breastfeeding, even partially, baby will still get many of the immune and other health benefits transferred through breast milk.

If I’m breastfeeding, how soon can I feed baby breast milk from a bottle?
First, you want to make sure baby is getting proper nutrition to grow and thrive. Generally, it takes a few days for milk production and the let down reflex to occur, and then it may even take a few weeks for breastfeeding to become well established and for you to feel confident about breastfeeding. For this reason, many pros recommend waiting three to four weeks to introduce a bottle. It’s often comforting to know baby latches on well to the breast and there are no feeding issues before you start introducing the bottle.

Expert: Jen Trachtenberg, MD, known to her patients as Dr. Jen, is a board-certified pediatrician, cofounder of The Baby Bundle app and a nationally renowned parenting expert and author of two parenting books.

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