How to Use a Breast Pump: Step-by-Step for New Mums

By BABYGO® | Published: 2026-10-14

Category: Guías prácticas

A practical walkthrough of pumping for new mums: flange sizing, a realistic newborn schedule, cleaning routines, and safe milk storage you can actually keep up with.

Quick answer

Set up your pump with a correctly sized flange, start on the lowest comfortable suction in let-down mode, and pump 10 to 20 minutes per side or until milk flow slows. For a newborn, aim for roughly 8 sessions in 24 hours if you are pumping instead of feeding, and always clean parts that touch milk after each use.

Get the flange size right before anything else

Most pumping pain and low output comes down to flange size, not the pump itself. Measure the diameter of your nipple base in millimetres, then choose a flange only 2 to 4 mm larger. A flange that is too small pinches; one that is too large pulls in areola and leaves milk behind. If your size changes in the first weeks, which is common, re-measure rather than pushing through discomfort.

Build a pumping schedule that fits newborn life

A newborn typically feeds 8 to 12 times in 24 hours, so if you are pumping to build or replace feeds, mirror that rhythm: about 8 sessions, including at least one overnight, because prolactin levels are higher at night. If you are pumping once in the morning to build a stash alongside breastfeeding, one session after the first feed of the day is usually the most productive. Spacing matters more than session length, so protect the gaps rather than stretching a single pump.

Clean parts daily and store milk safely

Wash all parts that contact milk in warm soapy water after each use, rinse well, and air-dry on a clean towel. A daily sanitise is sensible for newborns. For storage, fresh expressed milk keeps around 4 hours at room temperature, 4 days in the back of the fridge, and 6 months in a deep freezer; label every container with the date and use the oldest first. Thaw in the fridge, never on the counter, and never refreeze.

Make the session comfortable enough to repeat

Pumping is easier when your body is supported and your clothes are not fighting you. A hands-free bra, a cushion behind your back, and a drink within reach all reduce the tension that slows let-down. If you are pumping overnight or in the early days when you are still bleeding, soft high-waisted bottoms that sit above your tummy and do not dig in make sitting through a session far less miserable.

Your step-by-step pumping routine

Wash your hands and assemble the pump: Check the flange is the size you measured, push the valve and membrane firmly into place, and connect the tubing or cup as your pump requires. A loose valve is the most common cause of weak suction. If suction feels weak, re-seat the valve before turning the dial up.
Start in let-down mode on low suction: Begin with the faster, shallower pattern for the first one to two minutes, then switch to expression mode and increase suction only until it is comfortable, not painful. Pain is a signal to stop and resize, not to push through.
Pump 10 to 20 minutes per side: Stop when flow slows to drips rather than streams. If you are double pumping, 15 minutes total is often enough; if you are single pumping, switch sides when flow slows. Longer is not better; a 30-minute session usually just adds soreness.
Label and store what you collected: Pour into a clean container, write the date on it, and move it straight to the fridge or freezer. Use the oldest milk first and never refreeze thawed milk. If you will not use it within 4 days, freeze it now rather than later.
Clean every part that touched milk: Wash in warm soapy water, rinse thoroughly, and air-dry on a clean surface. Sanitise once a day while your baby is a newborn. Tubing usually only needs rinsing and drying unless milk has entered it.

Comfort items that make pumping sessions easier

BABYGO® Postpartum Knickers: Made from eco-friendly Tencel Modal with a seamless, high-waisted, C-section-friendly fit that sits gently above the incision line and gives light compression and support. Pumping means a lot of sitting, often overnight in the first weeks; a waistband that does not rub or roll down keeps those sessions tolerable while you heal.
BABYGO® Comfort+ Maternity Leggings: Made from breathable bamboo fabric with a seamless design and a gentle compression pocket for lightweight support through every trimester. If you are pumping at work or on the go, leggings you can pull down one-handed without pinching make a rushed session much quicker.
BABYGO® Sleepsuit & Sleeping Bag: A zip-up sleepsuit and sleeping bag bundle with fold-over hands and feet, designed for calmer bedtimes and simpler night-time changes. Faster night changes mean you get back to your pump or back to bed sooner instead of losing an hour to a wriggly baby.