How much breast milk do I need to express for my baby?

The answer is: It depends

Accurate, but not very helpful. However there are a couple of different guidelines that I found useful while breastfeeding:

Method 1: Average Intake

Method 2: Calculate

Approximate Conversions:

1oz = 30ml    2.2lb = 1kg

Take your baby’s weight in pounds and multiply it by two and a half or three times. Then, divide this number by the total number of  feedings a day to arrive at the approximate feeding amount, in ounces, for each feed.

 Formula in pounds and ounces:

Baby Weight x 2.5 = Daily Min                Baby Weight x 3 = Daily Max

Daily Min / Feeds per day = Min Feed

Daily Max / Feeds per day = Max Feed

Approximate amount per feed = Between Min Feed and Max Feed

Example: For a 10lb baby who feeds 8 times a day (includes night feeds)

10 x 2.5 = 25    10 x 3 = 30

So the baby will probably be drinking between 25oz and 30oz per day (in a 24 hour period).

25 / 8 = 3.125      30 / 8 = 3.75

So the baby will probably be drinking between 3oz and 4oz at each feed.

——————

Formula in kilograms and ml:

Baby Weight x 2.2 x 2.5 x 30 = Daily Min    Baby Weight x 2.2 x 3 x 30 = Daily Max

Daily Min / Feeds per day = Min Feed

Daily Max / Feeds per day = Max Feed

Example: 4.5kg baby who feeds 8 times a day (includes night feeds)

4.5 x 2.2 x 2.5 x 30 = 742.5       4.5 x 2.2 x 3 x 30 = 891

So the baby will probably be drinking between 742.5ml and 891ml per day (in a 24 hour period)

742.5 / 8 = 92.8125     891 / 8 = 111.375

So the baby will probably be drinking between 90ml and 120ml at each feed.

———————

Of course every baby is different, but this gives you somewhere to start. Try the approximate amounts and if the baby is still hungry try increasing it by 1oz or 30mls at a time.

TIP: Use an electric pump as they are easier to use and you can get more milk in each session. The ABA (Australian Breastfeeding Association) has some pumps that they recommend, check out their website.

Also many chemists will hire out pumps, definitely try before you buy so you get one that works for you.