You don't ever choose to switch your baby from breastfeeding to formula. The decision usually comes because one of more things are not working for you and your baby. You aren’t producing enough milk, your baby isn’t latching properly, your baby isn’t getting enough to eat, you’ve had mastitis for the 5th time in two weeks, the hormones are making you crazy or any other myriad of reasons. For me it came with Lulu when she just was not latching & was becoming so hungry that she couldn’t sleep. I’m not into starving newborns (is anyone?) and so we switched to pumping and formula. With Zelda it happened a little more gradually. She was latching but as a premie feeding would make her so sleepy, that we added in a bottle of baby formula instead of her tube feedings.
The next question after switching from breastfeeding to formula is which formula is the best formula for babies? I would love to tell you that X baby formula is the best but the honest answer is that there is no unilateral best formula. Baby formula, like everything with babies, doesn’t have a one size fits all solution. What works for one baby may not work for another. Do you use a lactose based baby formula or a lactose free? Organic or regular? You may need to try more than one brand or type of formula based on how your baby reacts to the formula.
With Lulu the first one we tried worked well for us, however she ended up on a feed thickener later on to help with her aspiration. There is now a formula with thickener included that can also help with reflux. Did you know there is also a grass-fed milk based formula? Did you ever think that you might be considering what the cows eat that provide the milk for the baby formula? No, you didn't? Neither did I. Good grief, when did things get so complicated?
At the end of the day just remember the best baby is a fed baby and the best baby formula is the formula that works for your baby.