After tons of research and trial and error, you’ve finally decided on which bottle is best for your baby. Congrats! It’s a huge deal. If your baby is doing well on a specific bottle, there’s no need to keep switching or spending money on other ones. But one thing you do need to be aware of is that as babies grow, the nipple size for each bottle changes to adapt to their growing needs.
If your baby is a premie or a newborn, there are a few variations you can try, there’s size 0 slow flow and regular size 0. Most babies can tolerate the standard size 0 start size until they’re 3 months old, but if you find that your baby is gagging while drinking from the bottle, you may want to try the slow flow nipple to see if that works better for them.
Here’s your nipple and bottle guide for every phase from 0-12 months:
The newborn nipple should be the perfect size for your newborn, unless, like we mentioned above, if you have a premie who needs a little more time and can’t handle the flow, it’s best to switch to a slow flow size zero. Most regular newborn nipples have the size 1 on them.
This is typically known as size 2. (note: some bottles say medium flow) This nipple has 2-3 holes in it making the flow of milk to your baby a little faster. Unsure if your baby is ready at 3 months? If they suddenly start to cry during feeds when they didn't before, it could be that they’re frustrated that the flow of milk isn’t coming in fast enough and they’re working extra hard to get the supply they need. If this happens, it’s time to switch to #2. As they reach closer to 6 months and are drinking more than 4 oz, it may also be time to switch to larger bottles.
6 Months +
When they reach 6 months, you can start switching the nipples out for size 3, they should also be on bigger volume bottles (typically 8 oz bottles). The best time to move to a size 3 nipple is if your child is starting to sit up, are on solid foods or if the pediatrician is recommending adding some extra powder to the formula to thicken the milk.
9 Months +
If you notice your baby is taking unusually long to take a bottle, it’s time to size up to level 4. If your baby is picking up finger food and eating it, drinking water from a sippy cup or if the pediatrician is recommending adding some extra powder to the formula to thicken the milk, it’s time to go to level 4 nipple.
Most pediatricians will recommend starting to transition your baby off of baby bottles and towards sippy cups once they hit the one year mark and start to transition more towards whole milk. Don’t worry if your baby isn’t ready for this, it’s a big change for them. If the transition takes 6 months to do, that’s perfectly normal as well.