Recently I haven't been able to produce as much milk as my DD needs. Luckily I used to have an over supply so I had a freezer stash of milk. But I've cut into that stash and realized that I'm going to have to supplement. So how does formula supplementing work? Should I mix formula with breast milk? Or, make one of her feedings entirely formula? And, what formula do you recommend? I briefly looked at the store and there are so many options.
Since I'm currently breastfeeding, we give her vitamin D drops - is this still necessary if I'm supplementing with formula? (This is more of a question for my pedi, but I'd like to know your thoughts until I can call tomorrow.)
I should add that I pump every day and usually we feed her expressed milk in bottles. Thanks!