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Breastfed Baby Not Gaining Weight

All was going great- so I thought. Little did I know, my 4 month old was falling off of the curve for weight. Our breastfed baby not gaining weight was a huge surprise.

Breastfeeding had been going wonderfully. He was happy after a feed, and he was sleeping well.

At 4 months, we were on a 4 hour schedule. This schedule was going great with 5 feedings, and 3 naps. He was even sleeping through the night after turning 4 months old. Things were going smoothly and I was pleased with his progress with everything.

At his 4 month appointment, however, I was told he hadn’t gained enough weight. I discussed it in this post outlining his development at 4 months.

The doctor was not concerned and told me he’d tell me if he was hungry.

And so, we went home and continued on.

Then there was a change. His poop was the sign for us. He suddenly wasn’t pooping. If/when he did poop, there was no substance to it. It was minimal amounts, green, watery, and didn’t have those little seedy things that breastfed poop has.

I knew that not pooping for up to a week was normal for breastfed babies. I knew that the color change could also be normal. But, I also knew it was different for him.

And so, I decided to take his temperature. It was LOW (97.1).

That concerned me. As a preemie, they kept a close eye on his temperature. When it was low in his first month, coupled with some gurgling noises in his chest, we were sent to the emergency room.

And so, we called the pediatrician. We were told it was nothing too urgent, but that they’d like to see us the next day.

happy 4 month old baby doing tummy time

At the appointment the next day, the focus quickly turned from the low temperature, to his lack of weight gain. In the 2 weeks since his 4 month appointment, he’d only gained 3 oz.

The doctor explained to me that the low temperature could be normal and we’d just keep an eye on it, but that the lack of poop coupled with his lack of weight gain was a huge concern.

The two issues combined indicated that he may not have “any excess waste to void.” It meant he was hungry and not getting enough food.

She asked me to add a feeding during the day, and one at night.

After getting home and discussing things with my husband, we gave her a call back and asked if it might just be better to supplement with the high calorie formula we’d been given in the NICU.

She loved that idea, since we wouldn’t have to disrupt his schedule or sleep habits.

The Plan for Our Breastfed Baby Not Gaining Weight

breastfed baby not gaining weight things to do immediately

Supplement with High Calorie Formula

After each nursing session throughout the day, we offered a few ounces of Enfamil 22 calorie Premature Baby Formula.

William gobbled it right down on the first try. My heart sank as I knew in that moment he hadn’t been getting enough to eat.

After the next few feedings, however, he wouldn’t take the formula.

We rationalized that it was his evening feedings that he wasn’t seeming interested in lately anyways, so maybe he just wasn’t hungry and would do better the next day.

I decided to switch the order. I gave him formula first, just to see if he’d take it on his empty belly. He was mad- so mad.

Find the Enfamil 22 Calorie Formula here:

Booby Tubes
Scale for Weighted Feeds
Avent Naturals
Enfamil 22 Cal Formula
Booby Tubes
Scale for Weighted Feeds
Avent Naturals
Enfamil 22 Cal Formula
Booby Tubes
Scale for Weighted Feeds
Avent Naturals
Enfamil 22 Cal Formula

He cried and pushed it away. He did this several times. Finally he’d take it, however. Then I’d breastfeed after. My goal was to get him used to the formula for a day or so and then I’d switch the order back.

This worked great. He was taking the breast milk and the formula with ease pretty quickly.

Weighted Feedings

I also took it upon myself to order a scale. I was interested to see how much milk he was actually getting from me.

My plan was to weigh him, then feed him, and then weigh him again.

The Scale We Used for Weighted Feeds:

Booby Tubes
Scale for Weighted Feeds
Avent Naturals
Enfamil 22 Cal Formula
Booby Tubes
Scale for Weighted Feeds
Avent Naturals
Enfamil 22 Cal Formula
Booby Tubes
Scale for Weighted Feeds
Avent Naturals
Enfamil 22 Cal Formula

The difference in the before and after weights would be the ounces that he’d gotten in breast milk.

I’d then feed formula, and weigh him a third time to see exactly what he’d taken in formula as well.

I did this for two days.

What I discovered broke my heart.

Data Collection on Breast Milk Intake

happy 4 month old holding lovey

I collected data for two days. It was clear there was an issue.

There were times that William would feed for 20 minutes and only get a couple of ounces from me.

Never was he getting enough.

Totals for the two days averaged 16 ounces of breast milk. This is far under the goal of about 24 ounces in a 24 hour period.

Luckily, he was making up the difference in formula. He was taking enough breast milk and formula combined to reach the 24 ounce goal.

Thank goodness! I was so happy to see this.

Correcting the Issue of Our Breastfed Baby Not Gaining Weight

4 year old feeding 4 month old a bottle

With the data in hand, I just didn’t feel comfortable knowing that he wasn’t getting enough breast milk, and I couldn’t believe he’d been seeming so happy!

It’s so hard when you are breastfeeding to know if anything is going on. You don’t see the milk- you don’t know how many ounces your baby is getting. You just have to trust and go on your baby’s temperament.

William’s temperament had been fine. I was devastated to know that he’d truly not been getting enough, however.

Related Posts Worth Reading:

NICU preemie challenges and benefits
Breastfed Baby Not Gaining Weight
4 month old schedule

Our options at this point for correcting the issue were pretty simple:

1- Breastfeed and supplement without using the scale.

2- Continue weighted feeds, and supplementing with formula.

3- Switch entirely to formula and stop breastfeeding.

4- Pump, feed and supplement with formula as needed.

5- Try to increase my supply.

I would be too nervous to just breastfeed and supplement without the scale. I knew I’d never trust my supply again, and that I’d end up being a slave to the scale. It was going to be stressful to say the least.

If you are looking for ways to increase your supply by the way, here is a great post on power pumping.

I’ve never responded well to pumping, and it takes up so much time. It would be unfair to our 4 year old for me to be spending so much time pumping and feeding.

Increasing my supply with methods that are hit and miss (unproven), would be a long battle. This would be stressful and delay William getting what he needs.

I could try to up my supply while supplementing, but even that is just delaying things and causing unneeded stress.

Switching to formula and stopping breastfeeding seemed like the best option for everyone.

We’d know he was getting enough and have much less stress, and well- he’d be getting enough and growing well.

And so, we made the call.

I sit here this morning with engorged boobs that are ready and wanting to feed my baby. My heart hurts that this is happening so suddenly.

I’ve never been one to like breastfeeding. I feel more like a cow than I ever wanted LOL! But when I stop, I cry. The emotions and sadness are unexpected.

There’s a sweetness- a bond. There’s a connection that happens when you breastfeed your baby. And so, I can’t deny it. I cried- several times. It’s hard to stop without time to mentally prepare.

This last week has been a whirlwind and quite sudden.

Two weeks ago, I thought I’d be breastfeeding for a full year. I thought things were going so well. Here we are, 1 day away from William turning 5 months old, and it’s done.

I feel so sad that we are done breastfeeding. Mostly I feel sad that our baby wasn’t getting enough, and that my body had failed him. I also feel so relieved that we a have a solid plan moving forward.

Yesterday was William’s full day of formula. He did great. He’s doing great.

We go in for a weight check in two weeks. Hopefully, he is making his way back onto the curve and making up some ground.

Products We Are Using for Formula Feedings

As for the scale, it’s getting returned. My sanity and our child’s growth is much more important than him getting breast milk.

We stocked up on Enfamil 22 calorie formula for premature babies. Luckily, we found a fellow NICU mom that had leftover stash. We paid $5 a can, instead of the $20 retail price.

Needless to say, we bought all of the cans from her!

We had a few bottles on hand that we’d never used.

Products We Used for Feedings

Booby Tubes
Scale for Weighted Feeds
Avent Naturals
Enfamil 22 Cal Formula
Booby Tubes
Scale for Weighted Feeds
Avent Naturals
Enfamil 22 Cal Formula
Booby Tubes
Scale for Weighted Feeds
Avent Naturals
Enfamil 22 Cal Formula

After giving them a try, we really like the Avent Naturals. I first tried these, because he’d been using the Avent pacifiers previously (he no longer uses pacifiers at all). I figured he might like the same brand/style of nipple.

He took right to it. The flow is nice and slow and the nipple is soft. Both are great for transitioning from breastfeeding to bottle.

Formula Feeding Pros and Cons

4 year old bottle feeding 4 month old

The negatives of formula feeding:

The positives to formula feeding greatly outweigh anything negative.

My heart will move on from the sadness I feel right now from having to stop breastfeeding.

Hopefully the measles outbreak will come to a halt. Luckily, there are only 4 confirmed cases here in Maryland (which I was told by our pediatrician is one of the most highly vaccinated states). If anyone reading this is someone that doesn’t vaccinate your children, I strongly urge you to reconsider.

Our son can’t yet get the vaccination since he’s not old enough. He will no longer be protected through breastfeeding… and so he’s at risk. This is the only negative to having him on full formula.

The positives of formula feeding:

I KNOW he’s getting enough food.

I know he’s getting everything he needs.

Feeds are faster.

It is less stressful.

I still get sweet moments feeding my baby.

My husband and daughter now ALSO get sweet moments feeding him!

Note: If your baby is refusing a bottle, here are some great tips.

Effects of Our Baby Now Getting Enough Food

William is now pooping again!

It’s weird poop. It smells. It’s not a color I’m used to- it’s formula poop!

Pooping means he’s getting enough food, so although it’s way stinkier than breastfed poop ever was- I’ll take it!

He’s got a diaper rash.

I’m guessing he’s got a diaper rash simply because of the diet change. It’s already getting better after about 3 days.

His metabolism seems to be kicked into gear.

He’s eating well and wanting lots! He’s even waking once in the middle of the night again.

I think he’s waking mostly because he’s pooping in the middle of the night. I then change him, since he’s pooped and has a diaper rash. I try and get him back to sleep without eating. It’s about 50/50 if he’ll let me.

He’s hungry since he’s so awake.

So, I feed him a couple of ounces.

Unfortunately, he’s waking around 4 am. This means that, if he eats, he’s not hungry enough to take a full feeding at 7 am.

If he doesn’t take a full feeding, he’s hungry before his next feeding and not napping well.

It’s causing him to be all off!

If he doesn’t eat at 4 am, however, his schedule is still working perfectly.

So, I am just trying to give him as little as possible and get him back on track.

4 Feedings a Day

He’s still taking 4 feedings a day.

Now that I know and can see how many ounces he’s getting, I’ll soon get a better feel for what he’s wanting each feed.

So far, it appears that he’s wanting around 5-6 ounces each feeding.

This puts him around 20-24 ounces total for the day.

This is much better than what was happening with breastfeeding. We’ll see how his weight changes at his two week checkup!

How to Stop Breastfeeding

I honestly did not think my boobs would get so engorged. My supply wasn’t the greatest (which by the way I think was due to my first period coming around the 4 month mark), so I figured it would be pretty easy to drop cold turkey.

It was not. It’s painful.

15 hours after my last nursing session, I was in so much pain.

I’ve been through this before, so I’m powering on.

When our second child died, my milk came in with nowhere to go.

The best things to do to stop milk production:

Do not express ANY milk.

Expressing milk tells your body you need milk production, so it will keep making more.

Wear a comfortable, supportive bra.

Keep your breasts cold.

Warmth stimulates milk production. Cold will help the inflammation.

I bought this item with our first born called “Booby Tubes”. They are gel free heat/ice packs. I keep them in the freezer. They fit right into my bra and are super comfortable.

Put cabbage leaves in your bra.

I know it sounds weird. It is. But it works. Keep the cabbage leaves cold in the refrigerator. Place them directly in your bra ALL DAY. Switch them out when they lose their chill.

There is supposedly something in the cabbage leaves that helps with the inflammation and stops the milk production.

This is the single most helpful thing (and yes, also the oddest).

Take Tylenol and Ibuprofen.

Tylenol for the pain, and Ibuprofen for the inflammation. Now that you aren’t breastfeeding you don’t have to worry about what medication you take! It will help!

To the Mama Going Through This

If you are in a similar situation with your breastfed baby not gaining weight, you can do this. Follow your mama gut. Choose the path that is right for you and your baby. It is ok. None of this is your fault.

breastfed baby not gaining weight 2

How To Troubleshoot- Breastfed Baby Not Gaining Weight

A common issue that breastfed babies encounter, is not getting enough breast milk, and therefore not gaining enough weight. This guide will explain how to troubleshoot the problem at hand.


  1. Immediately start supplementing with formula to make sure your baby's intake is optimal.
  2. You may need to offer the formula FIRST, if your baby refuses to take a bottle. Offer a couple of ounces in addition to your nursing session.
  3. Once baby is used to the formula and taking the bottle, offer breast first.
  4. Do weighted feedings to see how many ounces of breast milk your baby is eating. (weigh, feed, weigh again- the final weight minus the starting weight is the amount of milk in ounces).
  5. Talk with your doctor about your findings and come up with a plan.


Options if breast milk supply is low, or baby isn't getting enough:

1- Breastfeed and supplement without using the scale.

2- Continue weighted feeds, and supplementing with formula.

3- Switch entirely to formula and stop breastfeeding.

4- Pump, feed and supplement with formula as needed.

5- Try to increase supply in addition to supplementation.

Choose the option that makes the most sense for your family and consult your doctor. In any case, continue to follow up with doctor for weight checks.

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