How To Master Pumping Breast Milk: Cleaning Your Breast Pump Guidelines – Part 5

Pumped breast milk can become contaminated with viruses or bacteria

how to clean the breast pump
  • Save

This is a series on how to master pumping breast milk. You can read the other articles of the series here:

Breast milk nourishes your infant with the best possible nutrition. Pumping breast milk is a fantastic option to provide your baby with milk while you work or travel.

As a working mother, I understand the stress of maintaining the balance of pumping enough milk, cleaning the pump parts, and maintaining my workload.

However, cleaning the breast pump pieces and bottles are essential for your baby’s health.

While breast milk gives your baby plenty of essential nutrients, pumped breast milk may become contaminated by viruses or bacteria.

It is necessary to wash and disinfect equipment used for milk expression and storage. By not properly cleaning and storing your breast pump parts, your baby is at risk for infection.

  • Save

A Story About an Infected Baby

In 2017, a baby was born at 29 weeks. The preterm newborn developed meningitis that destroyed brain tissue after becoming infected from the outside of a pump.

The infant will have lifelong developmental delays. When they looked for the cause of the infection, they linked it to the outside cover of the breast pump at the mother’s home.

While mom was trying hard to do what was best for her baby, the external surface of the breast pump was the source of her baby’s illness.

There was also the same bacteria located in the sink drain. This means that placing clean pump parts in the sink after washing may transfer bacteria to your pump and your baby.

There are important steps to help keep your baby safe from the risk of infection. Premature or ill babies are mainly at risk for significant illness.

According to the Centers for Disease Control, the best possible way to minimize the risk of infection for baby regarding breast pump parts include the following steps.

Before You Pump

  1. Wash your hands with soap and water, scrubbing for at least 20 seconds. If you’re not sure how long this is, hum or sing the “Happy Birthday” song twice. If soap and water are not available, you can use hand sanitizer, but keep in mind that soap and water is the preferred method of cleaning.
  2. Assemble your clean breast pump parts. As you are putting them together, inspect each component to ensure there is no mold or dried milk.
  3. Wipe the pump down with sanitizing wipes or a disinfectant. There have been multiple instances of the breast pump transmitting an infection to the breast milk.

After You Pump

  1. When you’ve completed pumping, safely store your breast milk in a designated storage bag or bottle. If your flange detaches from the rest of your pump parts, you can use it as a funnel to ensure every drop of milk gets into your storage container.
  2. Some workplaces, NICUs, and hospitals provide a breast pump that is safe for many mothers to use. If you are using a shared breast pump, wipe it down again.
  3. Take apart the empty bottles and pump parts and inspect for mold or broken pieces.
  4. Rinse all pump parts under warm water to remove breast milk.

The CDC has approved washing all pump parts in one of the following ways:

Place the pump parts and bottles in the dishwasher. Read the manufacturer’s breast pump parts directions to ensure they are dishwasher-safe. When in doubt, hand wash or use the top rack.

  • Disassemble the breast pump parts and place in the dishwasher in a basket or mesh laundry bag, so they don’t fall into the bottom of the machine.
  • Run the dishwasher using hot water and the heated drying cycle to sanitize the breast pump parts and kill the maximum amount of germs.
  • Wash your hands with soap and water before removing the clean breast pump parts.
  • Remove the pump parts from the dishwasher, checking each one to ensure that they are completely dry. If not dry, turn the pump parts upside down on a clean dish towel or paper towel to air-dry thoroughly. Do not use a dish towel to dry the items as it may transfer infectious agents to the pump parts.

Wash all parts with hot water and soap

  • Use a washbasin and bottle brush dedicated only to your breast pump parts. Using a dish basin can cause cross contamination to your infant.
  • Do not put pump parts directly in the sink because studies show bacteria in sink drains can contaminate the pump at both your home and in the hospital. These viruses and bacteria can cause significant harm to your newborn, particularly if they are at risk of having a weakened immune system.
  • Add dish soap and hot water to the washbasin.
  • Scrub the breast pump kit parts vigorously with a bottle brush.
  • Rinse by holding the pump parts under the water to remove all dish soap.
  • When you have finished washing all of the breast pump parts, wash and dry the washbasin and bottle brush in the dishwasher or with hot water and soap. You should clean the bottle and basin at a minimum of every few days.
  • Dry the pump parts- this is an incredibly crucial step. Turn the pump pieces upside down or on a clean dish towel or paper towel. Do not use a dish towel to dry items because it may transfer bacteria or virus to the pump parts.
clean your breast pump to prevent bacteria infection
  • Save

There are microwave bags that are safe to use for sanitization. You can also boil the bottles. I do this any time my baby has an illness or we are sharing thrush.

When breast pump bottles are not thoroughly cleaned and dry, bacteria remains and can multiply. Improper cleaning of breast pump parts puts babies at risk of contamination of a significant illness.

A systematic review demonstrated that washing pump parts with hot water and soap, using a dishwasher, and boiling the pieces are each acceptable forms of cleaning pump parts and stopping the transmission of infection.

The key steps are washing the parts to remove all traces of milk, rinsing the soap, and making sure each section is dry before storing.


Giving your baby breast milk nourishes them and promotes a healthy gut. However, breast milk can transmit bacteria and viruses to your little one if you are not careful.

By following the above steps, you can keep your breast pump parts clean. When you wash your pump parts carefully, you are keeping your baby safe.

how to clean the breast pump
  • Save

Written by Caitlin Goodwin

Caitlin Goodwin is a board certified nurse-midwife, runs the family travel and autism blog, Typically Twitterpated and is a mom to four children. In her spare time, she and her family follow a gluten-free diet and share a love of all things travel, especially Disney.