Healthy infants come in a range of sizes. Still, infant growth tends to follow a fairly predictable path. Consider these general guidelines for infant growth in the first year:
- From birth to age 6 months, a baby may grow 1/2 to 1 inch (about 1.5 to 2.5 centimeters) a month and gain 5 to 7 ounces (about 140 to 200 grams) a week. Expect your baby to double his or her birth weight by about age 5 months.
- From ages 6 to 12 months, a baby may grow 3/8 inch (about 1 centimeter) a month and gain 3 to 5 ounces (about 85 to 140 grams) a week. Expect your baby to triple his or her birth weight by about age 1 year.
Your baby's doctor will monitor your baby's growth at routine well-baby exams, likely charting your baby's growth on a standard growth chart. Keep in mind that many healthy babies go through brief periods when they stop gaining weight or even lose a little weight. A doctor would likely be concerned only if an otherwise healthy baby doesn't gain weight from one well-baby exam to the next. Your baby's position on the curve in a growth chart isn't as important as the trend of the curve overall.