Variations in the normal growth pattern
Although most children follow the normal patterns of growth, a small number of children have growth patterns that differ from the typical model. These less common but normal patterns of growth include:
Growth rate changes in infancy
Delayed growth in normal children (constitutional growth delay)
See also: Familial short stature
Growth rate changes in infancy
It is not unusual for normal children under 2 years of age to cross percentile lines in either direction. This happens because the factors that affect growth before birth are different from those that govern growth after birth.
Upward or downward shifts
Babies who are small at birth often shift to a higher growth channel during the first few months of life, as they "catch up" to their own growth potential. On the other hand, large or average-size babies who have short parents may have slower-than-expected growth during the first months of life as they settle into their own growth channel. A downward shift in growth during the first 1.5 to 2 years of life may not be a cause for concern if the baby is healthy and thriving, if he or she has a good diet, and if height and weight are shifting together.
Ruling out problems
The healthcare provider who sees such a baby may ask many questions about the baby's habits and behavior, and will perform a careful examination to make sure there are no physical problems. The baby's height and weight should be measured carefully and marked on his or her growth chart every 3 months.
Achieving steady growth
At some point between the child's first and second birthdays, the child should begin to maintain steady growth along the "new" percentile channel. After this new growth curve is established, height and weight should be checked and plotted on the growth chart every 3 to 6 months until age 3, and every 6 to 12 months after that. As long as the child is healthy and growing at a normal rate, no special treatment for growth is needed.
Delayed growth in normal children (constitutional growth delay)
This type of growth pattern is one of the most common causes of parental concern about growth. Constitutional growth delay is the term used to describe children who:- Are small for their age (growth is at or below the 5th percentile line on the growth chart)
- Are growing at a normal or near-normal rate
- Have a delayed bone age (usually 1 to 4 years behind their chronological age)
- Are late in entering puberty
- Have no signs or symptoms of diseases or conditions that affect growth
Catching up after puberty
Constitutional growth delay is more common in boys than in girls. These children often are shorter than other children their age before they start school. If good growth records are available, one or more periods of slow growth during early childhood may be seen. These children do not catch up in their growth until after the pubertal growth spurt. They continue to grow at the slow, steady rate of childhood for longer than most of their friends.When they finally enter puberty at about age 15 for boys and 14 for girls, they have a normal growth spurt and normal sexual development. Their adult height usually is similar to that of their parents. Constitutional growth delay sometimes runs in families. Often there is a history of delayed growth and adolescence in the child's parents and other relatives.
