Pumping and Storing Breast Milk

Breast pump and bottles on a desk
Jamie Grill / Getty Images

Four weeks is often when breastfeeding mothers begin to think about pumping and storing extra breastmilk. That's when most babies are breastfeeding well and you can usually be less concerned about nipple confusion from taking a bottle of pumped breastmilk.

If you are pumping before then, it is usually because you are trying to increase your breast milk supply or because your baby isn't latching well.

Benefits of Pumping

What are the benefits of pumping?

One benefit is that you will have breastmilk to feed your baby if someone else is watching her. This is especially helpful if a breastfeeding mother is going back to work and can help avoid formula supplements.

Having pumped breastmilk can also provide you with something to feed your baby when you are on the go if you don't want to nurse in public.

And of course, pumping can be very helpful if you ever need to boost your breastmilk supply.

Remember that breastmilk production is mostly based on 'supply and demand.' So any extra pumping you do, in addition to your baby's nursing, can simulate an increased demand and help increase your breastmilk supply.

Some mothers even prefer to pump, relying on exclusive pumping so that they know exactly how much milk their baby is getting.

Downsides of Pumping

Are there any downsides to pumping?

The main downsides are the possible discomfort of pumping if you are not doing it properly, the costs involved in purchasing a breast pump, pumping supplies, and bottles. There is also the time involved in pumping and cleaning the breast pump and bottles.

Pumping can be done in place of or after/between a feeding. It depends on the mother's goals with pumping.

Types of Breast Pumps

While the most basic "pump" to express milk is your hand, other types of breast pumps include:

  • Manual or hand-held breast pumps
  • Battery powered pumps
  • Electric pumps
  • Hospital-grade pumps (can often be rented)

There are also single (one breast) vs. double (both breasts at the same time) breast pumps.

While most insurance plans now cover the cost of a breast pump because of the requirements of the Affordable Care Act, they typically just pay for a basic electric pump.

Hospital-grade breast pumps are most useful for establishing or increasing a milk supply. An electric breast pump (non-hospital-grade) works well when returning to work.

Storing Pumped Breast Milk

If you have a good supply of breastmilk and your baby is nursing well, you may quickly build up a supply of pumped breastmilk that you now have to store safely.

Common breastmilk storage guidelines state that breastmilk can be safely stored for:

  • Up to 4 hours at room temperature
  • Up to 24 in a cooler with ice packs
  • Up to 4 days in the refrigerator
  • Within 6 months is best but up to 12 months is acceptable in a freezer that is 0°F (-18°C) or colder.

Be sure to write the date on the containers so that you will know to use the oldest ones first.

Using Pumped Milk

So what do you do with all of the pumped breastmilk?

While you can try to arrange a donation to a breastmilk bank if you aren't going to be able to use it all, you will mostly want to thaw, warm, and feed it to your baby.

It is important to do that safely, such as by:

  • Allowing frozen breastmilk to thaw in the refrigerator over several hours (up to 24 hours)
  • Thawing the frozen breastmilk container in warm or lukewarm water
  • Warm the thawed milk by placing it under lukewarm running water for a few minutes and then shake it up and test the temperature before feeding it to your baby

You should not thaw frozen breastmilk at room temperature, refreeze leftover breastmilk that has already been thawed, or warm it in a microwave.

3 Sources
Verywell Family uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. U.S. Department of Health and Human Services. Your Guide to Breastfeeding.

  2. U.S. Centers for Medicare & Medicaid Services. Breastfeeding benefits.

  3. Centers for Disease Control and Prevention (CDC). Proper Storage and Preparation of Breast Milk.

By Vincent Iannelli, MD
Vincent Iannelli, MD, is a board-certified pediatrician and fellow of the American Academy of Pediatrics. Dr. Iannelli has cared for children for more than 20 years.