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Newborn Weight Loss & Gain

What's expected, when to worry, and how to track

newbornhealthfeedingbaby care

Weight Loss Is Normal at First

Almost all newborns lose weight in the first few days after birth. This is not a sign of a problem. It is caused by the loss of excess fluid and the fact that the baby is taking in small amounts of colostrum before the milk comes in. The expected weight loss is up to 7 percent of birth weight. A baby born at 7 pounds (3,175 grams) could lose up to 7.8 ounces (222 grams) and still be within the normal range.

When Weight Loss Is a Concern

Weight loss greater than 7 percent of birth weight requires evaluation by the pediatrician or lactation consultant. Weight loss greater than 10 percent is considered significant and may require intervention, such as supplementation, feeding therapy, or evaluation for underlying medical issues. The care team will monitor weight closely if the baby is losing more than expected.

When the Baby Should Regain Birth Weight

Most babies regain their birth weight by day 10 to 14. Some take a few days longer. After the milk comes in (usually day 3 to 5), the baby should begin gaining weight steadily. The expected rate of gain after the first week is about 5 to 7 ounces (140 to 200 grams) per week for the first 3 months. Your pediatrician will track this at well-baby visits.

How to Track

What Affects Weight Gain

When to Call the Doctor

Resources

The American Academy of Pediatrics has growth charts and feeding guidelines on HealthyChildren.org. The CDC also provides WHO growth standards for infants. Talk to your pediatrician if you have concerns about your baby's weight gain.