Why Your Breastfed Baby Is Not Gaining Weight

Sleeping newborn
Yuko Hirao / Stocksy United

Most breastfed babies will gain weight in a consistent and expected pattern as long as they latch on well and feed often. But, if you're breastfeeding and your newborn is gaining weight slowly or inconsistently, he may not be getting enough breast milk.

Adequate nutrition is, of course, essential to your baby growing and thriving. Here's what to look for and what to do if you think your baby is not gaining weight as expected.

Typical Weight Gain for Breastfed Babies

All babies grow at their own pace, but baby weight gain does tend to follow a fairly consistent pattern.

Breastfed newborns can lose up to 10% of their birth weight during the first week. Then, by the time a child is two weeks old, he should regain the weight he lost. After that, for the next three months or so, breastfed babies gain about an ounce a day.

Of course, every newborn is different, and some children normally grow more slowly than others. So, as long as your baby is breastfeeding well and his health exams are on target, a slower weight gain may not be an issue.

Cause for Concern

Weight gain is the best sign that a child is getting enough breast milk. When a baby is gaining weight slower than expected, it could mean that she's not getting enough.

If your newborn is not back to her birth weight in two weeks, or she's not gaining weight consistently after that, it may indicate that there's a breastfeeding issue preventing your child from getting enough breast milk.

Using an At-Home Scale?

Weighing your baby at home is not a substitute for taking your baby to the pediatrician. It can, however, be a great way to work with your child's doctor to be sure your baby is gaining a healthy amount of weight.

Reasons Your Baby May Not Be Gaining Weight

There are a number of reasons why your baby may not be getting enough breast milk to gain weight consistently. Some of these include:

Poor Latch

A good latch allows your child to remove breast milk from your breast without getting tired and frustrated. If your baby is not latching on correctly or is latching on to just your nipple, she won't be able to remove the breast milk very well.

Infrequent Breastfeeding

Breastfeed your newborn at least every two to four hours through the day and night for the first six to eight weeks. If he wants to breastfeed more often, put him back to the breast.

Too-Short Nursing Sessions

Newborns should breastfeed for about 8 to 10 minutes on each side. As your child gets older, she won't need to breastfeed as long to get the breast milk she needs. During the first few weeks, however, try to keep her awake and actively sucking for as long as you can.

Pain or Discomfort

If your baby is not comfortable because of a birth injury or an infection such as thrush in her mouth, she may not breastfeed well, and therefore she may be gaining weight slowly.

Low or Delayed Breast Milk Supply

Some mothers may have a delay in the onset of breast milk production, which means production is either slow or late entirely. Other mothers experience chronic low milk supply, which can have several causes that may work individually or in combination to reduce the amount of milk a child receives when breastfeeding. The good news is that a low milk supply can often be improved pretty easily.

Although it's not as common, some medical issues can cause a true low breast milk supply. You may still be able to increase to a true low milk supply, but it's more difficult. It needs to be treated and followed by a doctor.

Risk Factors for Weight Gain Difficulties

While most newborns and infants will breastfeed well and gain weight, some babies are more likely to have difficulty breastfeeding. When a child is at risk for breastfeeding difficulties, the chances of growing and gaining weight at a slower pace are higher.

Being Born Premature or Near Term

Smaller babies or those born before 37 weeks may not have the strength or energy to breastfeed for a long enough time to get all the breast milk they need. They are also more likely to be sleepy and experience medical issues such as jaundice or dehydration, which can make breastfeeding even more difficult.

Oral Challenges

It's can be difficult for any baby to latch on if his mother has hard, engorged breasts and/or large nipples. However, infants with small mouths or a physical issue such as a tongue-tie or a cleft lip and palate can have latching troubles regardless.


Newborns with jaundice may have a yellow tone to their skin. It can make babies very sleepy and not interested in breastfeeding.


Infants with reflux spit up or vomit after feedings. Not only do they lose some of the milk from feeding, but the acid from the reflux can irritate their throat and esophagus making it painful to breastfeed.


Infants with an illness or an infection may not breastfeed well. They may not gain weight or they may even lose weight, especially if they have diarrhea or are vomiting.

Neurological Issues

Neurological issues such as Down syndrome can impede a baby's ability to latch and nurse properly.

What to Do If Your Baby Is Gaining Weight Slowly

If you are concerned about your child's weight gain, or lack thereof, it is essential to take your child to see his healthcare provider as soon as possible. The doctor will examine, measure, and weigh your baby and give you a sense of what is expected for your child at her age. He will also advise you as to the strategies that may work best for you and your child, and when to come back for another check-up.

Some that you may want to consider or that may be suggested to you include:

  • Check your child’s latch. Make sure your baby is latching on to your breasts correctly. You can ask a friend with breastfeeding experience, your doctor, a lactation consultant, or the mothers in a local breastfeeding group for help if you need it.
  • Breastfeed often. Nurse your baby every two to three hours and whenever she shows signs of hunger. Don't put your baby on an every three- to four-hour feeding schedule like a formula-fed baby. Since breast milk is more easily digested, breastfed babies need to eat more often.
  • Avoid using a pacifier (at first). Stay away from the pacifier for the first four to six weeks. If your baby sucks on a pacifier instead of nursing at the breast, she won't be getting as much breast milk. A pacifier can also tire your baby out, so she may not nurse as well when she does get to the breast. Once your baby is breastfeeding and gaining weight well, you can offer the pacifier if you want.
  • Keep your baby awake during feedings. Try to keep your baby actively breastfeeding for about 20 minutes at each feeding. If you have a sleepy newborn, try to keep him awake by tickling his feet, changing your breastfeeding position, changing his diaper and burping him, or using the switch nursing technique.
  • Address supply issues. If the problem is your breast milk supply, take steps to increase your milk production. Besides breastfeeding more often, you can pump in-between feedings, add some milk-boosting foods to your meals, or try breastfeeding herbs or teas.
  • Consider supplementing. If your baby's doctor thinks it's necessary, you may have to supplement your baby with additional feedings of either your pumped breast milk or infant formula. If you have a premature baby, you can breastfeed first, then offer the supplemental milk after each feeding. You can also try to pump and separate your foremilk from your hindmilk. Hindmilk is higher in fat and calories, which can help your baby gain more weight.

Should You Stop Breastfeeding?

As long as it's safe for your baby, you can continue to breastfeed exclusively while working closely with your healthcare provider. Depending on your situation, you may decide to partially breastfeed or breastfeed just for comfort. If you do wean from the breast, you can choose to exclusively pump, switch over to infant formula, or give your child a combination of both. The choice is always yours.

Infant formula is a safe alternative. And for many moms, it's the only way to ensure that they have a healthy child who is growing and gaining weight well. Achieving that goal is what's most important. If you need to change your breastfeeding plan to achieve, feel good that you tried your best and you're doing what you need to do for yourself and your child.

Was this page helpful?
Article Sources
Verywell Family uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. American Pregnancy Association, "Monitoring Your Newborn’s Weight Gain."

  2. Stanford Children's Hospital, "Slow or Poor Infant Weight Gain."

  3. Centers for Disease Control and Prevention, "How Much and How Often to Breastfeed."

Additional Reading
  • Dewey KG, Nommsen-Rivers LA, Heinig MJ, Cohen RJ. Risk factors for suboptimal infant breastfeeding behavior, delayed onset of lactation, and excess neonatal weight loss. Pediatrics. 2003 Sep 1;112(3):607-19.

  • Riordan, J., and Wambach, K. Breastfeeding and Human Lactation Fourth Edition. Jones and Bartlett Learning. 2014.

  • Cadwell, Karin, Turner-Maffei, Cynthia, O'Connor, Barbara, Cadwell Blair, Anna, Arnold, Lois D.W., and Blair Elyse M. Maternal and Infant Assessment for Breastfeeding and Human Lactation A Guide for the Practitioner Second Edition. Jones and Bartlett Publishers. 2006.
  • Lawrence, Ruth A., MD, Lawrence, Robert M., MD. Breastfeeding A Guide For The Medical Profession Eighth Edition. Elsevier Health Sciences. 2015.
Related Articles