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Baby Spitting Up Curdled Milk – How to Know if it is Normal or Not!

Mom’s question:
My baby boy is 5 weeks old. He is eating 4 oz every 3-4 hours. He is spitting up a lot. He was on breast milk, but after he was spitting up what looked like curdled milk his doctor said to try formula. He is doing the same thing, so switching to formula didn’t help at all. I’m not sure what to try now?

Brandi (Sparr, FL)

Baby Helpline:

Curdled Milk In Baby’s Vomit, Normal Or Not?

First of all, the milk becomes curdled when mixed with the acidic stomach fluid. So curdled milk in itself is normal and not a problem. Many young babies spit up a bit of curdled milk now and then.

But curdled milk in combination with very frequent vomiting may be a sign that something is not completely right.

Here are a few possible reasons for excessive spitting up of curdled milk:

  • Your boy has intolerance to for example lactose or milk protein. If this is the case, then switching to formula will not help at all unless you give him special formula that caters for these problems. Two possible types of formula that may work are hydrolysate formula, which is hypoallergenic and most often tolerated by babies with milk protein allergy, or low lactose formula, which can help your baby if he is lactose intolerant. (Links to Amazon, where you can check them out.)

    However, it is entirely possible to continue breastfeed a baby who is allergic to cow’s milk! All you have to do is to eliminate cow’s milk from your own diet.

  • He may suffer from acid reflux. This is quite a common condition among newborn babies, where the gastric juices containing acid can travel back from the stomach into the throat – painful. (You’ll find several tips for feeding a baby with reflux in this thread. Switching to formula can help slightly since the formula is a bit thicker than breast milk. But it is a fairly minor difference!
  • Pyloric Stenosis – a condition where the outlet of the stomach is too narrow for the foods to travel over into the intestines. Projectile vomiting of milk that may or may not be curdled, weight loss, and constipation are some of the signs of pyloric stenosis. This condition needs treatment and surgery.(You can read more about pyloric stenosis at KidsHealth.org)

This is not a full list, of course, just some examples. It may very well also be that nothing is wrong with your baby and that he simply is a baby who spits up a bit more than the average infant. If he is gaining weight and doesn’t appear to be in pain, he is likely to be fine.

If it is reflux, changing to formula doesn’t generally help. Instead, things like not feeding your baby too much at the time, feeding him in an upright position, avoid foods (for you if you breastfeed) that can aggravate reflux such as citrus, tomatoes, fatty foods, spicy foods, and carbonated drinks. (Learn more about foods to eat and avoid while breastfeeding here.) There is also some medication available.

Obviously, no one can tell if your baby does have reflux without examining him and there may be other reasons for his spitting up.

I think you should take him back to his doctor (or maybe to another one if you don’t think you get enough support from this one).

Simply telling you to stop breastfeeding is not, in my opinion, a good advice.

There are not many reasons to think that this would solve the problem (as you have already noticed), and while formula is a good substitution for breastmilk, it is still a substitution and several of the benefits of breastfeeding will be missed.

Good luck!

Find comments below.

Comments for “Baby Spitting Up Curdled Milk”

Oct 30, 2012

Baby spitting up
by: Anonymous

Okay, if the baby is spitting up a lot I would take the formula down a little bit like to 3.5 oz. My babies are almost 4 months old and take 4 oz. every three hours. I do believe that is too much for a five week old. Good luck!

Mar 09, 2013

I think its sad…
by: Anonymous

I think it’s very sad that a professionally trained person such as a doctor would tell a mother not to breastfeed her child because of spitting up. There are many factors…such as a cow milk intolerance in your milk…so you would need to cut out diary products. Since you changed from breastmilk to formula…then the problem would not stop there because formula is made mostly from cow milk. I would advise switching back to breastmilk which can help your child recover inside and out when dealing with problems in this big world such as allergies. If you do not plan to switch back i would suggest a goat milk formula base (goat milk digests in the human system within 2-4 hours…cow milk takes 8 and more) or at least try an organic formula or soy based. Although these can be a little more, your baby would greatly benefit from it. Good luck and my advise it to find another pediatrician! It has been medically proven for a very long time that breast milk is what was designed for the infants ultimate help and support during life. Babies do not even develop an immune system alone for the first 6 months of life, they rely on yours to fight for them during that time. Good luck!

Sep 17, 2013

Spitting up worries!

by: Anonymous

My daughter spit up all the time when she was first born until about 8 months. I only breast fed, and I was worried she was spitting up almost everything that was going in. We found the problem to be reflux, and although she continued to spit up after the medicine it wasn’t as much. Once you start her on foods she will be better, but don’t stop breastfeeding!!

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