Breastfed babies gain weight differently than formula fed infants. Breastfed babies typically gain weight more quickly during the first six months, then gain weight a bit more slowly the second six months.
Here are the average amounts breastfed babies should gain throughout the first year:
- Babies 0-4 months should gain 5.5 – 8.5 ounces per week.
- Babies 4-6 months should gain 3.25 – 4.5 ounces per week.
- Babies 6-12 months should gain 1.75 – 2.75 ounces per week.
It is normal for babies to lose weight in the first few days immediately following birth. Weight loss between 5-7% during the first 3-4 days after birth is normal and expected. Weight loss equal to 10% is sometimes considered normal. However, babies who lose 10% or more of their birth weight should be monitored very closely to ensure they are getting enough milk. There are a few possible reasons a baby may lose more than 5-7% of their birth weight which have nothing to do with how much milk the baby is receiving. If the mother has had an induction, a cesarean birth, or an epidural longer than 6 hours, the additional fluids passed into her will in turn get passed into the baby, thus resulting in a “false” birth weight. A “false” birth weight can exaggerate the baby’s weight loss leading to concerns about milk intake. Many experts are pushing for baby’s weight to be assessed 24 hours after delivery, rather than immediately after birth to help determine the actual birth weight. This practice may ease mother’s concerns about milk supply and their baby’s weight gain.
Babies who have lost 10% or more of their birth weight should have a routine weight check performed at 5 days, so that any developing problems can be caught and remedied early. By day 5, babies should be gaining rather than losing weight.
Breastfed babies are expected to regain their birth weight by 10 days to 2 weeks after delivery. Babies who lost 10% or more of their birth weight, or who were sick or premature, may take longer to regained their birth weight. If your baby has not regain his or her birth weight by 2 weeks, it is important to assess how breastfeeding is going and seek help from lactation consultant.
It’s important to note that babies should be weighed on an infant scale, preferably naked. Weighing baby on a home scale will not give you an accurate measurement. If you have any concerns about your baby’s weight gain, you should request an appointment with your baby’s pediatrician. If supplementing is necessary, ask your baby’s pediatrician if you can supplement with your own breast milk while working to increase your milk supply. Then, seek help with breastfeeding and/or pumping from a local lactation professional.
If your exclusively breastfed baby’s weight gain falls within or is GREATER than the averages listed above, you’re doing great! This is a sign that your milk supply is sufficient.