Sterilizing bottles and pump parts, simplified

Bottle and pump-part hygiene matters most in the early months, when a baby's immune system is still developing — but it doesn't need to be complicated.

Before first use

Sterilize new bottles, nipples, and pump parts once before their first use — boiling for 5 minutes, a steam sterilizer, or a microwave sterilizing bag all work.

Day to day

After the first use, most guidance shifts to a simpler routine:

1. Rinse parts in cold water right after use to keep milk from drying on.
2. Wash in hot, soapy water with a dedicated bottle brush, or run through the dishwasher on a hot cycle if parts are dishwasher-safe.
3. Air-dry completely on a clean rack before reassembling — trapped moisture is where bacteria grows.

When to sterilize again (not just wash)

• Baby is under 3 months old, was born prematurely, or has a weakened immune system.
• After an illness in the household.
• Roughly once a day is a reasonable middle ground many caregivers settle into for young infants, even without a specific reason.

A few practical tips

• Keep a separate small brush just for nipples and pump valves — their narrow parts trap residue that a regular sponge misses.
• Fully disassemble pump parts and bottles before washing; anything left assembled can hide milk residue in the joints.
• Store dry parts in a clean, covered container rather than loose in a drying rack overnight.

When to check with your pediatrician

If you're ever unsure whether a piece of equipment is still safe to use — cracked bottles, cloudy plastic, worn-out valves — it's simpler and safer to replace than to keep sterilizing.