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Preparing infant formula- Your go-to guide
After I found myself formula feeding the twins. I decided to look for all of the different ways to preparing and feeding infant formula.
Of course, I found myself super overwhelmed with everything that the internet has to offer. Some resources were helpful and some not so much.
Because I know as a mom time is limited I created this one stop resource to help answer all of your questions about preparing baby formula.
So what do you need to know to properly prepare formula?
- Clean bottles
- Read the back of formula labels
- Shake or stir
- How to make formula in bulk
- Formula feeding guidelines
- Formula feeding positions
- FAQs to preparing infant formula
How to make baby bottles?
The actual preparation part is easy. The time-consuming part is all the different steps you need to remember.
1. Clean bottles
The number one step is making sure that we have washed the bottles.
I know we don’t wash bottles every time we feed because hello who has time to wash so many times. But do remember that after formula sits in the bottle for so long bacteria can start to grow.
So before preparing any new bottle remember to wash them.
Either hand wash in the sink or put in the dishwasher
How to hand wash bottles
- Always remember to wash your hands first
- Disassemble the bottle. Yes is a pain but you need to disassemble ALL of the parts
- Rinse bottle with hot water
- Get a bottle brush and wet it
- Put soap in bottle brush and wash
- Rinse bottle again with hot water
- Set bottle in a drying rack to air dry
- Rinse bottle brush
- If you used a bucket them also rinse the bucket for the next use
PRO TIP: Want to save time? Get a bucket that you will use for your bottles ONLY and fill it with hot water and soap. Put the bottles and parts inside the bucket and proceed with the rest of the steps.
This is a faster and easier way to wash bottles and without worrying about a bottle touching your sink. Because let’s face it sinks can be pretty nasty. Especially as a mom who doesn’t have time to clean it 50 million times.
How to wash bottles in the dishwasher?
- Wash your hands
- Disassemble bottle parts
- Line bottle parts in the dishwasher
- For smaller parts use a dishwasher container or mesh.
- Just so the parts don’t go everywhere.
- If possible run the dishwasher in hot water
Should you sterilize your baby’s bottles?
Yes and No… This is where I put my nursing hat on.
If you have a healthy newborn then just properly washing the bottles is fine.
However, if your newborn has medical issues or if you maybe have twins that were born prematurely. As an extra safety measure, you might want to sterilize the bottles.
2. Read the back of formula label
The next step to preparing formula is to make sure you read the back of the formula label. Why?
Because not every formula has the same formula to water ratio. For the most part, they follow the 1:2 ratio. Which is one scoop formula: 2 ounces of water. But some might be different.
To be safe read the formula label and do as directed.
3. So what water do you use?
As far as what water you can use. There are several options.
You can get a filter, buy distilled water, use bottle of water, or boil water.
Do you have to boil water for formula?
The answer is YES and NO.
The American Academy of Pediatrics (AAP), says that it depends on where your water is coming from. So if you aren’t sure if your water is safe then boil it or consult with your pediatrician.
If you want to go for the convince factor then you can buy the gallon of distilled water which every major grocery store sells for like $1 or buy bottles of water.
Distilled water is great for my mommas whose babies are in daycare. With the twins, this was the easiest way to provide water to the daycare.
Another solution that we used is to get a filter. We purchased a filter and its replacements and put them in our kitchen sink.
This is great because is convenient for anything not just making bottles.
4. Shake or Stir
There are two ways in which you can mix formula. It all depends on what easiest for you or will be better for your baby
Shake: Place nipple and bottle cover on. Hold the bottle with one hand and do an up and down motion. Do this until everything is completely mixed.
Worry about bubbles? Then you need to stir.
Stir: Hold the top of the bottle and twirl the bottle slowly in a circular motion. OR use a spoon and mix slowly until the formula is dissolved
Specific example to preparing formula
If you’re a visual person like myself then sometimes is easier to put all of the steps together.
Let’s pretend we are making a 4oz bottle.
- Wash your hands
- Get a clean bottle
- Pour 4 ounces of water into a bottle
- Add 2 scoops of formula.
- Remember to follow the ratio written at the back of the formula
- Close bottle by adding nipple and top
- Shake or stir
- Feed baby
5. How to prepare formula in bulk
Newborns eat pretty frequently and sometimes is much faster and time-saving to make formula in bulk.
The easiest way to make formula in bulk is by using a formula mixing pitcher. Dr. Brown has a formula mixer pitcher that makes the process easier.
I personally never used it because like I mentioned my twins went to daycare so I couldn’t benefit from making formula ahead of time.
But the reviews can’t lie.
So let’s go back to making the formula in bulk. The pitcher can hold up to 32 ounces so remember that.
If you want to make 32 ounces:
- Wash your hands
- Grab Dr Brown’s pitcher
- Pour 32 ounces of water
- Grab formula
- Again if your formula is a 1:2 ratio then add 16 scoops
- If your formula is not 1:2 ratio follow the back of the formula label
- Use mixer that comes with a pitcher and mix away
Have your own pitcher?
A. If for some reason you already have a pitcher at home then find out how many ounces that pitcher is if it doesn’t come label already.
B. Use measuring cups to help you get the exact amount you need.
let’s say you want to make 30 ounces with your own pitcher:
30 ounces= 900 ml
Did you get it? You multiply the number of ml by the number of ounces. If you are unsure you can literally go to google and put the numbers and it will calculate it for you.
Ml is the easiest way to calculate because most measuring cups give you mls.
The above photo of my measuring cup only comes up to 500ml but I need 900ml.
Measure the water until the 500ml pour into the pitcher and then measure the other 400ml and pour into the pitcher.
As far as the formula goes follow the back of the label. But if it’s 1:2 ratio then in order to make 30 ounces you will need 15 scoops of formula.
Mix with a large enough spoon that you have and you’re done.
Hope this wasn’t too complicated. Only wanted to provide another way if you already have a pitcher at home.
6. How to heat formula
As far as heating formula you have several options:
- Choosing not to heat
- Bottle warmer
- Plain warm water
Let me tell you that I have tried all three of these methods with my babies and they didn’t seem to have a preference over the other.
Keep in mind that once you warm up a bottle it is only good for an hour. So make sure you warm it right before your baby is going to eat.
If your baby doesn’t finish the bottle and it’s been longer than an hour then toss it.
Choosing not to heat
This is probably the most time-saving out of all of the three options. If you use distilled water, filter water, or even a room temp bottle of water then no need to heat.
Not heating a bottle means feeding on the go just got ten times easier. If you are always on the go and if you’re trying to maximize your time then don’t start warming the bottle.
A room temp bottle or a cold bottle is not going to kill or hurt your baby. If you never introduce them to something they will not know any better.
I have truly only used my bottle warmer with my first baby. He was exclusively breastfed and the warmer was only used when someone else was feeding him and needed to warm up my breastmilk.
But bottle warmers are annoying. If you’re going to go this route then buy the cheapest one you can get. We had the Babies R US brand. It’s not supposed to be fancy. It just needs to be able to warm milk so don’t waste a lot of money on one.
Yes, a bottle warmer is going to warm it to be the appropriate temperature for your baby but guess what? As a good habit to have you still going to use the back of your hand to check if the milk is too hot or not.
If I could do it again I would probably have not bought one. Because once my husband figured out the warm water method we never looked back.
Warm water method
By far this is my favorite way to warm a bottle. Especially with twins. I can get a bucket big enough and warm both bottles at the same time.
This is great even if you don’t have twins.
If you’re trying to save money this is the way to go. Plus you’re still going to use the back of the arm method to check for the right temperature.
This can easily be done on the go as long as you find some type of container and fill it with warm water.
7. Formula feeding guidelines
As far as guidelines to follow. This is where I put on my nurse’s hat. How much to feed, how often to feed, etc. It all depends on your baby and it should all be baby-led at least at the beginning.
Do keep in mind that. If your baby has health issues such as jaundice, weight loss. etc. Like my twins did. Then your pediatrician might have you on a strict schedule in order for your baby to gain weight quickly.
The guidelines I’m giving you are for healthy newborns ONLY
How much formula you should be feeding?
So this is going to be a very broad answer but for a healthy newborn, you should be focusing on hunger cues.
Newborns’ stomachs are tiny and for the first couple of weeks, they might not need much.
So they might drink as low as 5ml-30ml per feeding.
This leads me to:
How often should your newborn be bottle feeding?
Another broad answer. Every newborn is different and it can vary from every 1 to 3 hours. Because at the beginning you need to be focusing on hunger signs.
PRO TIP: Don’t let your newborn go longer than 6 hours without feeding. If they are going that long then wake them up and fed them.
Newborn hunger signs?
These are clues you’re looking for when your baby is hungry. Some common signs are:
- Hands sucking
- Suckin anything
- Rooting (which is when the baby just turn head around and is trying to suck on something)
- Crying- usually the last cue
How to know when you need to increase the baby’s formula?
If you haven’t figured out how much your baby typically drinks. Then start small and work up.
In the hospital, I usually told mommas to start with 1 ounce = 30ml and see what happens.
If your baby stops before the 1 ounce and is content, fell asleep. Then they are good.
If your baby is still trying to eat then you know that they are ready for more.
Start with 0.5-ounce increments. So if you started with 1 ounce and your baby drank it. The next time do 1.5 ounce and so on.
The moral of the story is to watch your baby an listen to their cues.
Consult with your pediatrician when in doubt
Your pediatrician is your new BFF. They’re a great resource. If you aren’t sure always consult with them. They know your baby and they will be able to suggest or create a schedule specific to your baby’s needs.
How to know if your baby is getting enough formula?
So what you need to pay attention to in order to know if your newborn is getting enough:
- Wet diapers
- Baby’s mood: is he/she happy after a feeding, falls asleep
- Is your baby gaining weight: Do remember that it’s ok for them to lose weight within the first two weeks but after that period of time is your baby starting to gain weight?
How many ounces does your baby need?
This is an estimate… Listen to your baby and also your doctor.
So roughly babies will drink about 2-2.5 ounces per pound. Meaning if your baby weighs 10lbs then they will drink 20-25ounces in a 24 hour period.
8. Formula feeding positions
Now that we learn everything about preparing formula. How do we feed our babies?
They are different positions. But I want to focus on the two that are easy and will also be very beneficial for reflux babies.
- Cradle: baby heads are placed in the crook of your arm. Your arm is titled up allowing the baby to be in an upright position. You will use your other hand, to feed the baby
- Use rocker/boppy: place baby in rocker or boppy. Strap baby and then proceed to feed bottle
Is it ok to feed the baby lying down?
It all depends on your baby. Remember the nipple of formula comes out faster than breastmilk.
Just pay atention to your baby. Do they cough, shock, or show signs of distress when you feed them laying down?
Then you’re fine. If you have a baby with reflux then this is a big no-no. Those babies need to sit up in order to better digest formula.
PRO TIP: for reflux babies not only should you feed them sitting up but leave them in a sitting up position for 30 minutes after feeding. This will give them a chance to digest the formula.
9. FAQs for preparing and feeding infant formula
Here are some of the most common questions when it comes to preparing a bottle of formula.
How long is the prepared formula good for?
Two answers to this question:
A. If bottle has been warmed and baby drank from it then is only good for an hour
B. If you made the bottle but the baby didn’t drink from it and you also didn’t warm it. Then you have 2 hours before putting it in the fridge.
Can you prepare baby formula in advance?
Yes. Scroll up because I show you how to do it.
Once formula is in the refrigerator how long is it good for?
You have 24 hours to use that formula before you need to toss it. HINT: Try to only make the amount of formula your baby usually eats in a 24 hour period. That way you don’t waste a lot of formula.
Can you reheat formula?
No. Once you warm the formula that’s it. Discard within an hour. Reheating formula increases the chances of bacteria developing.
Why do you need to discard formula after an hour?
Because the combination of the baby’s saliva and time increases the chances of bacteria development.
How much water and formula should you add? can you add more?
Follow the 1:2 ratio or whatever is in the back of your formula label. Do not add extra unless you consulted with your pediatrician first. Doctors or advanced providers can alter the formula in order to increase your baby’s calorie needs. But ONLY they can do it. Not you. So follow everything as directed on the back of the can.
Can cold formula upset your baby’s stomach?
If you haven’t introduced your baby to warm formula then there should be fine. The cold formula is not going to affect them in any way. However, if they have already had warm formula then it becomes a preference thing.
Final words for preparing infant formula
Preparing formula is not super complicated. The problem is that there is a series of steps we need to follow. Once you get in a rhythm it becomes second nature.
As always if you’re unsure ask your pediatrician they are the best person to answer any specific questions and concerns.
And if you ever have any questions feel free to use this bottle feeding guide as your resource.
Please let me know in the comments if you found this guide helpful.
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Tips to help you prepare and feed infant formula
I’m B the creator of Twins Made Easy. I’m an RN BSN MNN, wife, and mother to three kids (including boy/girl twins). Sharing and helping you survive twin life and more one coffee at a time. Read more
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