The Pump Rules

When following the Breastfeeding Rules, pumping is one of two ways to feed your newborn baby


  • Highest comfortable suction, not highest tolerable suction. Pain with pumping is not normal. More vacuum does not mean more milk. Always start on the lowest vacuum as you carefully place your nipples in the flange. Slowly turn vacuum up, checking in with yourself at each step up. Once you find the vacuum that feels “uncomfortable,” TURN IT DOWN to return the vacuum to comfortable. This is your highest comfortable vacuum. It may vary from pump to pump, so follow feel each time. 

Flange Fit

  • Best breast drain, most comfortable fit, nipple not rubbing.
  • Most lactating parents are comfortable in one of the two flanges that come with their breast pump:  medium 24/25 mm or large 27/28mm.  Some find they need a size larger or smaller than this.
  • To find your most comfortable and effective fit, try changing sizes, using a or using a pumping lubricant (store bought or olive oil or coconut oil)

Length Of Time

  • 10-30 minutes. If you seem to drain in 10 minutes or less, stay on for 10 minutes. Most lactating breasts need about 15-20 minutes each to drain. If your breasts have been filling for longer than 3-4 hours, you may need 25-30 minutes to drain your breasts.
  • In general, pumping for longer than 30 minutes is unnecessary and can feel excessive on your nipples, even if the flange fit is correct.


  • Frequency is more important than duration. Since newborn nursing behaviors are how a milk supply ios built, and since pumps are built to mimic nursing, the more frequent the demand, the more abundant the milk supply to follow.
  • How often you pump in a 24 hour period depends on the purpose of your pumping and how often you are nursing/directly latching the baby.
  • For the first 6 weeks, breasts need 8-12 times stimulations per 24 hours to build supply. Breasts should ideally go no longer than 5 hours during this 6 week period. 
  • Once milk supply is established, around six week postpartum, the number of times a day your breasts need to be stimulated in unique to your breasts, but will fall in the 6-12 range.  


  • Stimulate (fast) – the fastest speed your pump has is considered the “stimulation phase” this is the pattern of quick, short sucking newborns are known to enage in when they first latch onto the breast and are seeking to trigger a let down of milk to drink. When pumping, begin on the fastest speed and adjust to highest comfortable vacuum. After about 2 minutes, you should see a change in the rate at which your milk is coming out of your nipples. Drips may get bigger or more frequent, you may even see a spray of milk. When you see this change, switch to the expression/slower cycling speed. 
  • Express (slower)- some pumps, like most Medela pumps, only have two speeds. Other pumping, like the Spectra, have multiple slower expression cycles. Most spend 10-15 minutes on the slower expression cycle. 
  • If you are expressing, or the milk is flowing and you are collecting the milk, use the slower cycle.
  • If you are looking to “ask your body for more milk” use a higher speed stimulation cycle. If you notice milk flow slowing, you can try repeating the stimulation cycle in an effort to trigger a subsequent let down. Again, once you see milk flowing, switch to the slower cycle to collect that milk.
  • Seek help if you can’t seem to get a comfortable fit that drains your breasts well.

Flange Fit

  • The best flange fit is comfortable and effective. If your nipples aren’t rubbing and your breasts seem to be draining, the flange you are using is fine. 
  • If the flange fit feels irritating to the areola try lubricating your nipple before pumping with your breastfeeding nipple cream, coconut oil or a commercial pumping lubricant to decrease friction.