Expressing and effective expressing

What is expressing and when is it effective?

Expressing means removing milk from the breast by hand or pump. It can be done instead of or as well as breastfeeding. Expressing by hand is called manual expression. Pumping uses a machine or other device. There are advantages to each. Manual expression is very helpful for establishing the milk supply and electric pumping appears to be more effective for long-term expression. Whatever method mothers choose, expression needs to be effective in order to prevent the milk supply from decreasing and to prevent a range of painful problems caused by overfull breasts. Mothers are expressing effectively if they get the expected amount of milk in no more than 20 minutes on each breast, if the breasts feel empty after a session, if there is no pain with expression, and the milk supply does not decrease over time.

A) Describing expressing (pumping and manual expression)

Expressing is removing milk from the breasts. This can by done in two ways:

  1. Pumping (using a machine or other device to express milk).
  2. Manual expression (using the mother’s hands).

Expressing may be done instead of breastfeeding or in addition to it. Mothers sometimes express right after the baby’s birth to establish their milk supply or for other reasons as the baby grows. Expressing should be effective and sustainable (Becker 2016).  

Some mothers leak milk when they breastfeed. The leaked milk can be collected and stored for later use.

Once obtained, breast milk must be properly stored.

When possible, breastfeeding is preferred to expressing as the latter has risks.

B) Effective expressing

When expressing, mothers need to ensure they express effectively so that the milk supply does not decrease over time and to prevent a range of painful breast problems.

Signs that expression is effective include:

  • Expressing the expected amounts of milk.
  • Expressing for no more than 20 minutes on each breast.
  • Expressing often enough. Mothers should remove milk from the breast by breastfeeding or expressing at least seven times each day.
  • Feeling that the breast is emptied at the end of each expression.
  • Using proper techniques so that there is no pain with:

There are ways to make expression more effective, including:

Compared with breastfeeding, expressing can be a lot of work. Avoiding unnecessary effort is a key part of effective expressing. There are a few ways to decrease the effort of expressing, including a hands-free system for mothers who choose to pump.

C) Choosing a method

Mothers who want to or need to express have the following options: 

Hand and electric pumps increase and decrease suction in a way that mimics a baby’s sucking. These are piston type pumps. More recently constant suction pumps have been available. They have a bulb that is squeezed to create suction but have no other moving parts.

Effective manual expression only requires proper technique.  

The following table compares pumping to manual expressing.

Table: Comparing a Piston Pump, a Constant Suction Pump, and Manual Expression

There is only a small amount of research comparing breast pumps and manual expression.

In general, electric pumps are more effective once the milk supply is established (Meier 2016). Manual expression can be effective for obtaining colostrum and in establishing the milk supply before the mother’s milk comes in.

D) Pumping equipment

Mothers who are considering pumping need to:

  • Decide on a type and brand of pump.
  • Obtain a pump.
  • Make sure they have the right size of breast shield.
  • Ensure the pump is working.
  • Know how to pump.
  • Know how to clean pump parts safely.


Becker GE, Smith HA, Cooney F. Methods of milk expression for lactating women. Cochrane Database of Systematic Reviews 2016, Issue 9. Art. No.: CD006170

Meier PP, Patel AL, Hoban R et al. Which breast pump for which mother: an evidence-based approach to individualizing breast pump technology. J Perinatol. 2016 Jul;36(7):493-9