Re: Amount to pump for a 4 month old
Babies need 1-1.5 ounces per hour they are away from mom. Depending on how experienced your caregivers are with feeding breastfed babies it is very easy to overfeed them with a bottle. Breastfed babies are used to being able to control the flow of milk to some degree and with a bottle they can't, so they will often drink until the bottle is gone, whether they are hungry for it all or not. Most moms find it best to send 2-3 ounce bottles with a few 1-2 ounce top-off bottles just in case they are needed. Breastfed babies only rarely take more than 4 ounces at a time and the amount doesn't increase as they get older because your breastmilk changes in composition and gets more concentrated.
Here are some good resources to give you an idea of how much you'll need and an article about how to bottlefeed a breastfed baby you might want to share with your caregiver.
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