According to an article on kidshealth.com, the average height for 2-year-olds is 34 inches. However, a number of factors affect toddler height, and if a child is taller or shorter than average, that is no cause for concern. To track your child's health, she should be growing steadily and gaining weight and height at the same rate.
Height and Weight Ratio
For toddlers, a wide range of heights and weights are still considered normal. However, it's important that a toddler grows steadily in both height and weight. A 2-year-old should grow taller in proportion to his growth in height. If a child suddenly gains a lot of weight without getting much taller, this could indicate a problem. Likewise, growing taller without gaining weight is not healthy, either. So parents should be aware of their child's ratio of weight to height and the child growing bigger and taller. Babies experience a huge growth spurt in their first year, but after that, most children grow fairly steadily until around puberty, when the next major growth spurt occurs.
Genetics and Other Factors
A 2-year-old is generally about half of his adult height. Genetics, of course, are a major factor in determining height. Tall parents often have tall children, and vice versa. Some children also have a constitutional growth delay, which means they grow more slowly than their peers. These children may also experience puberty later, but they generally continue growing longer than their peers and reach an average height as adults. Also, children who are born prematurely are usually small babies and may still be smaller than other children at 2. Lack of adequate sleep or nutrition may also affect children's growth. Toddlers need 10 to 13 hours of sleep each day, including naps.
At regular checkups, a doctor charts a child's growth on a growth chart. For 2- to 20-year-olds, doctors record each child's height, weight and body mass index, using separate charts for boys and girls. A growth chart also shows average percentiles, collected by the CDC for these measurements, which indicates how a child compares to other children her age. A 2-year-old in the 90th percentile for height and weight is heavier and taller than 90 percent of other 2-year-olds. If a child's percentile ranking stays about the same over time, he is growing at an average rate. A sudden, drastic change in percentile might indicate a problem of some kind.
Causes for Concern
If a child abruptly moves to a different percentile for height or weight, this could indicate a problem. Sometimes a growth delay is the first indication of another health issue. Failure to thrive is a condition in which children, usually under age 3, show slower than expected growth. It may be caused by inadequate nutrition or digestive problems. Another possible cause of unusually slow growth is an endocrine problem, such as growth hormone deficiency or hypothyroidism. However, a smaller size than other children his age generally does not indicate a problem unless a child is growing at a significantly slower rate than his peers or than his previous rate of growth.