Once a baby is born, one of the parent's biggest concerns is making sure the baby is normal. A normal height and weight indicate the baby is healthy and growing. As only the doctor can indicate what is normal for a particular baby, regular checkups are required to be sure the baby is healthy.
Defining Normal Height and Weight
As all babies are born with different sizes, gestation, and DNA, it's impossible to identify one normal height and weight they should all hit. While their starting circumstances are all different, the growth is the one place where there is a normal expectation. Babies less than six months old are expected to grow at the rate of one-half to one inch each month, and between five and seven ounces a week.
At the age of three months, a female baby should measure somewhere around 60 cm long. In traditional measurements this is 23.6 inches long. Male babies should be about 61.5 cm or 24.2 inches long. These heights are the 50th percentile measurements for population comparison charts of babies 0 to 6 months.
Doctors will not expect preemies to follow these averages due to their unfinished gestation. They will have other criteria to reference in these circumstances.
At three months of age a baby boy should weight about 6.4 kg, or 14.1 lbs. A female baby should weigh 5.8 kg or 12.8 lbs. These weights are concurrent with the 50th percentile weights on most doctor charts used to chart infant growth.
Doctors will reference the so-called z-score and percentile charts to ensure the infant is within desired guidelines based on the infant's birth size and age.
How fast a baby grows and if it is normal is based on many factors. Factors may include whether the baby is being breastfed or uses formula. While up until six months breastfeeding is the only nutrition needed, some babies do not get enough milk, and it is difficult to measure what they are getting. Additionally, a doctor would want you to track how often the baby is eating and for how long, how often he urinates, the frequency, volume and consistency of bowel movements, and if you can measure it, how much the baby is getting at each feeding.
While most parents over-worry in the beginning of their child's life, there are some circumstances that would warrant concern. Babies should urinate at least 4 to 6 times a day. Those who are not getting enough to eat may not seem satisfied after a meal and may be whiny or hungry soon afterward. Bottle-fed babies should be eating 3 to 4 oz. per feeding 6 to 8 times a day, adding an additional ounce for every month after the first. Breast-fed babies should eat every 3 hours for at least 10 minutes each time.