If you compare your baby to others his age, you may worry that he isn't eating the right amount of food. In truth, however, there is no one ideal weight for all babies. Since all babies are different, your baby's ideal weight may be different from the ideal weight of other babies his age. The most important indicator of his health is that he grows at a steady rate and seems satisfied after full feedings.
Newborn Weight
Most full-term newborns weigh between 6 lbs., 2 oz. and 9 lbs., 2 oz., according to KidsHealth online. Babies who don't fall within this range are typically fine, but they may receive additional care from nurses and doctors after they are born just to ensure that they are healthy. Moreover, babies born before 37 weeks' gestation tend to be smaller than babies born within a few weeks of their due date.
Ideal Weight Gain
Babies typically gain between 5 and 7 oz. per week--or an average of 1 to 2 lbs. per week in their first 6 months--doubling their birth weights by the time they are 5 or 6 months, according to the Mayo Clinic. Between 6 and 12 months, babies may gain between 3 and 5 oz. per week--or an average of 1 lb. each month--to triple their birth weights by age 1.
Variations
Babies' genes, temperaments and eating schedules affect their weights, according to pediatric health expert Dr. Sears. For example, a baby with a slower metabolism, apple-shaped fat distribution and laid-back demeanor is more likely to gain weight faster than an active banana-shaped baby who has a quicker metabolism. However, the banana-shaped baby may catch up in weight if he is breastfed with no restrictions and the mellow apple-shaped baby is fed on a strict schedule.
Charting Weight
All babies' head circumferences, body lengths and weights are measured at regular doctor visits to assess their growth. After they are measured, they are plotted on a chart which averages all infants in the same developmental stages. A percentile is assigned to each baby based on rank. An infant in the 10th percentile for weight, for example, weighs more than 10 percent of infants his age and less than 90 percent of infants his age. Alternately, an infant in the 50th percentile is at the exact average weight of all infants his age. According to Merck online, a single percentile isn't significant in assessing health, but a huge drop or increase from last measurement may be of more concern.
Scheduling Doctor Visit
Parents concerned about their baby's weight should consult a pediatrician as soon as possible. However, the Mayo Clinic mentions that many healthy babies go through periods where they lose some weight or temporarily stop gaining weight.
