Re: milk storage/use question
Yes, but remember that the use-by date for the combined bottle is the one for the oldest milk in the bottle, not the newest. IIRC, previously frozen milk is good for 24 hours once it has been unfrozen. Fresh milk would be good for as long as 7 days in the fridge.
Are those bottles being given while you're at work? If so, separating the milk into smaller portions may confer advantages that are worth the hassle of the second bag/bottle. One of the biggest problems for working, pumping moms is overfeeding by daycare providers. Larger bottles mean that the adult who is giving the bottle doesn't need to pause the feeding in order to reach for the second portion of milk. Not pausing means that the baby doesn't get a chance to burp, or to think about whether or not he's really still hungry, and he may take significantly more milk than he actually needs. And despite the fact that the baby is eating a lot, fast feedings give baby less opportunity for comfort sucking, which can result in him acting hungry even after a very large bottle. At that point, the daycare provider will often ask for more and more milk, putting increasingly unreasonable demands on the mom, who is slaving over the pump.
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