Weight Loss in the Breastfed Baby

Information, Causes, and What You Can Do

Mother watching nurse weigh her newborn baby
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Breastfed newborns can lose up to 10% of their body weight during the first week of life. After that, babies gain approximately 1 ounce each day. By the time they are two weeks old, newborns should be back to their birth weight or even weigh a little more.

Your newborn is not getting enough breast milk and is losing too much weight if he:

  • Loses more than 10% of his birth weight
  • Continues to lose weight after the first week of life
  • Is still under his birthweight after two weeks

Causes of Weight Loss

Newborns who are breastfeeding can lose weight for a variety of reasons. They include:

  • Not breastfeeding enough: It is important to put your baby to the breast at least every 2 to 3 hours to stimulate a healthy milk supply and provide your baby with enough breast milk to gain weight.
  • An incorrect breastfeeding latch: When your baby isn't latching on correctly, he or she cannot efficiently remove enough milk from your breast to grow at a consistent, healthy rate.
  • An issue with your baby's ability to latch: If you have severely engorged breasts, large nipplesflat nipples, or inverted nipples, your child may have difficulty latching on. Babies can also have physical or neurological issues that interfere with their ability to latch on to your breast properly. As mentioned above, your baby will not be able to get enough milk without a good latch.
  • The use of a nipple shield: A nipple shield can be a great breastfeeding tool when used correctly and under the supervision of a doctor or lactation consultant. However, nipple shields that are not used correctly can prevent a baby from getting enough breast milk. They can also cause a decrease in your milk supply.
  • A sleepy baby: Sleepy newborns need to be aroused for feedings every 2 to 3 hours. Breastfeeding a sleepy baby can be a challenge, but it's very important to make sure that your baby is nursing often and getting enough breast milk to gain weight.
  • A late onset of milk production: A difficult birth, stress, or a retained placenta are some of the causes of a delay in milk production. Until your breasts fill up with milk, your baby will not gain weight.
  • A true low milk supply: Moms with certain physical or hormonal issues such as hypoplastic breasts, PCOS, hypothyroidism or a previous breast surgery may not be able to produce a healthy milk supply. If your milk does not come in by the fourth day postpartum, talk to your doctor and have an examination. In some cases, a true low milk supply can be corrected with treatment.

Things You Can Do

If your baby is losing weight or not gaining weight as expected, you shouldn't wait to ask for help.

Seek help right away if your breastfed baby is losing weight. Your health and the baby's health should be assessed, and you may need a lactation consultant.

Getting breastfeeding off to a good start can make all the difference in how successful you will be. Plus, correcting any issues right away helps to ensure your baby will get enough nutrition and fluids to stay hydrated and begin to gain weight.

Here's what you can do if your breastfed baby is losing weight.

  • Have your baby's latch evaluated by your nurse, a doctor, a lactation consultant, or a local breastfeeding support group.
  • See your doctor. Find out if there is a physical or hormonal issue that might be interfering with your breast milk supply.
  • Take your baby to the doctor to check for an illness or any other problems that could be interfering with breastfeeding. Infections, tongue-tie, jaundice, and other newborn issues can cause poor nursing and weight loss in infants.
  • Monitor your baby's weight.
  • Keep track of how many wet diapers and bowel movements your baby is having each day.
  • Breastfeed your baby very often, at least every 2-3 hours around the clock. If you have a sleepy baby, wake her up to breastfeed every three hours.
  • Breastfeed longer at each nursing session.
  • If your supply of breast milk is low, try to increase it by pumping. You can also ask your doctor or a lactation consultant about the use of galactagogues. Certain herbs, foods, and nursing teas may be helpful to increase a low milk supply.
  • It may be necessary to supplement your baby if your child continues to lose weight. Talk to your doctor about continuing to breastfeed along with supplementation. A nursing supplementer device can be used to be sure your baby is getting enough breast milk or formula while still nursing at your breast.
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Article Sources

Verywell Family uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial policy to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Kellams A, Harrel C, Omage S, Gregory C, Rosen-carole C. ABM Clinical Protocol #3: Supplementary Feedings in the Healthy Term Breastfed Neonate, Revised 2017. Breastfeed Med. 2017;12:188-198. doi:10.1089/bfm.2017.29038.ajk


  2. American Academy of Pediatrics. Warning Signs of Breastfeeding Problems. Updated November 2, 2009.


  3. McKechnie AC, Eglash A. Nipple shields: a review of the literatureBreastfeed Med. 2010;5(6):309–314. doi:10.1089/bfm.2010.0003


  4. Riddle SW, Nommsen-rivers LA. Low milk supply and the pediatrician. Curr Opin Pediatr. 2017;29(2):249-256. doi:10.1097/MOP.0000000000000468


  5. American Academy of Pediatrics. A Breastfeeding Checklist: Are You Nursing Correctly? Updated November 2, 2009.


Additional Reading

  • Lawrence, Ruth A., MD, Lawrence, Robert M., MD. Breastfeeding A Guide For The Medical Profession Eighth Edition. Elsevier Health Sciences. 2015.

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