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 one ounce each day. By the time they are two weeks old, newborns should be back to their birth weight or even weight 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 in the Breastfed Newborn

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

Things You Can Do

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

  • Seek help right away.
  • Have your baby's latch evaluated by your nurse, a doctor, a lactation consultant, or a local breastfeeding support group.
  • 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.


Academy of Breastfeeding Medicine Protocol Committee. ABM clinical protocol# 3: hospital guidelines for the use of supplementary feedings in the healthy term breastfed neonate, revised 2009.

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

Noel-Weiss J, Courant G, Woodend AK. Physiological weight loss in the breastfed neonate: a systematic review. Open Medicine. 2008;2(4):e99.

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