Newborn Weight Fluctuations: What to Expect

Dr. Ashley Pinchinat is a pediatrician at Maria Fareri Children's Hospital in New York. She shares her answers to common parent questions about newborn weight fluctuations below!

Congratulations on your new baby! There are so many things that you may have questions about and one if "Is my baby eating enough?" Whether you choose to breastfeed, formula feed, bottle, spoon, or something else, remember that fed is best.

How do I know if my baby is getting enough milk?

If your baby is comfortable after a feeding, then you know your baby has gotten enough milk. 


What is normal weight gain?

Your baby gains about an ounce per day for the first few months and should double their birth weight by 3-4 months. All of this will be relative to your baby's growth curve.


My baby lost weight. Is that ok?

It is perfectly normal for babies to lose some weight after birth. You will have an appointment with your doctor a few days after the baby's birth and again around the 1-2 week mark. Your doctor will look at the baby's growth chart and decide if any additional follow up is needed. 

If you're breastfeeding and the baby is losing more weight than expected, be sure to speak with a lactation specialist and your doctor about how the feeds are going. We will want to discuss the mother's milk production, the baby's latch, duration of feeds, amongst other things. Breastfeeding can be extremely difficult and your providers can help you walk through that path together.


What if my baby isn't gaining weight?

If there are any concerns with weight gain, you may be asked to supplement the baby temporarily or increase the calories in the formula. You can even add formula to breast milk to increase the calories. Work with your doctor to figure out what will work best for your family. 


My baby spits up SO much

It is normal for babies to spit up or have some degree of fussiness after feeds. Their tummies have to learn how to process their food AND poop it out. It's complicated stuff! Reason for concern would be if your baby is not gaining weight. If that's the case, your doctor will talk with you about keeping the baby upright after feeding, if any modifications need to be made to the mother's diet or formula, or if any medications need to be trialed.


Some signs of dehydration 

If your baby seems sleepier than usual, the soft spot on their head seems sunken, or is making fewer than 3 wet diapers a day, your baby would need to be evaluated immediately. Always speak with your baby’s provider with any concerns!


My nephew, Julian!
My nephew, Julian!
Me and my nephew, Julian!

My nephew, Julian!

My nephew, Julian!

My nephew, Julian!

About the author

I’m Dr. Ashley Pinchinat. I grew up in Brooklyn and have made my way through New England for school and training - MIT for undergraduate, Dartmouth for medical school, and residency at Baystate Children’s Hospital. I’m back in NY and am currently completing fellowship in pediatric hematology oncology at Maria Fareri Children's Hospital. My nephew, Julian, adds light to my life. Who knew peek-a-boo and animal sounds could spark so much joy?

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