What is Growth?

A child's physical growth refers to the increases in height and weight and other body changes that occur as a child matures. Hair grows; teeth come in, come out, and come in again; and eventually puberty hits. It's all part of the growth process.

What's Normal?

The first year of an infant's life is a time of astonishing change. During this time, a baby will grow rapidly. On average, babies grow 10 inches (25 centimeters) in length while tripling their birth weights by their first birthday.

Given all the growth that occurs in the first year of life, new parents may be surprised when their child doesn't continue to grow through the roof. But no child continues the rate of growth experienced during infancy. After age 1, a baby's growth in length slows considerably, and by 2 years, growth in height usually continues at a fairly steady rate of approximately 2 1/2 inches (6 centimeters) per year until adolescence. No child grows at a perfectly steady rate throughout this period of childhood, however. Weeks or months of slightly slower growth alternate with mini "growth spurts" in normal children. Kids actually tend to grow a bit faster in the spring than during other times of the year! A major growth spurt occurs at the time of puberty. Usually kids enter puberty between age 8 to 13 years in girls and 10 to 15 years in boys. Puberty lasts about 2 to 5 years. This growth spurt is associated with sexual development, which includes the appearance of pubic and underarm hair, the growth and development of sex organs, and in girls, the onset of menstruation. By the time girls reach age 15 and boys reach age 16 or 17, the growth associated with puberty will have ended for most teens and they will have reached physical maturity.

At the Doctor's Office

Beginning in infancy, a child will visit a doctor for regular checkups. At each of these visits, the doctor will record the child's height and weight on a growth chart. This chart shows the doctor and parents how the child's height and weight compare to that of other children the same age. This valuable tool can help your child's doctor determine whether your child is growing at an appropriate rate or whether there might be any problems.

What Can You Do?

There are several things you can do to help ensure that your child grows and develops normally. Make sure he or she gets the following, which are critical to your child's overall health and wellness:
enough rest - Sleep patterns vary by age and individual child, but most kids need an average of 10 to 12 hours of sleep per night. Sleep gives growing bodies the rest they need to continue growing properly.
proper nutrition - A balanced diet full of essential vitamins and minerals will help your child reach his or her full growth potential.

adequate exercise - Because obesity is a growing problem in kids, parents should make sure that their children exercise regularly, as well as receive proper nutrition. Bicycling, hiking, in-line skating, sports, or any enjoyable activity that will motivate your kid to get moving will promote good health and fitness and help your child maintain a healthy weight.

Talking to Your Child About Growth

Children differ in growth and development during childhood - just like adults, some kids are taller or shorter. Generally, girls hit puberty earlier than boys, although some girls might lag behind their peers in breast development and the onset of menstruation. All of this is usually completely normal.

Try to avoid comparing growth among siblings or other children. Drawing attention to a child's height, for example, will only make that child feel self-conscious about his or her size. Encourage your child to accept his or her own growth and development. Explain that some children grow and develop at different rates - and late bloomers generally will catch up eventually. Children have many questions about growth, from why their teeth fall out to difficult or potentially embarrassing topics like breast development or perspiration. Answer questions honestly and even initiate conversations about growth to help your child understand the many changes he or she is facing. This will help your child accept the changes positively. If you're uncomfortable discussing these topics or avoid the subjects altogether, your child may interpret that to mean there's something shameful about the changes he or she is going through and may be less likely to talk to you about any concerns.

Kids who are short often face teasing by peers and may need help coping. You can help a short child by supporting his or her self-esteem. For example, although it might be difficult for a small boy to make the football team, emphasizing alternatives, such as soccer or tennis, may make him feel better about himself and what he can do. A small teen might have concerns about dating, driving, and participating in sports. It's important to try to understand your child's feelings and to keep the lines of communication open. Another thing you can do to boost your child's mood is to encourage activities that don't focus on height or weight. Emphasize special talents or individual qualities, such as musical aptitude or a love of literature.

If You Suspect a Problem

Parents sometimes become concerned about their child's growth and development, but it can be reassuring to know that most children who are short or delayed in development are healthy and normal. For example, shorter parents tend to have shorter children and not all kids develop at the same rate.

If you're concerned about your child's growth, the first step is to consult your child's doctor, who can thoroughly evaluate your child and your family history and, if necessary, order some basic lab tests to see if there may be a medical condition affecting growth. The doctor may choose to monitor your child's growth more frequently on a growth chart.

Bone Growth

Bones grow in length at the epiphyseal plate by a process that is similar to endochondral ossification. The cartilage in the region of the epiphyseal plate next to the epiphysis continues to grow by mitosis. The chondrocytes, in the region next to the diaphysis, age and degenerate. Osteoblasts move in and ossify the matrix to form bone. This process continues throughout childhood and the adolescent years until the cartilage growth slows and finally stops. When cartilage growth ceases, usually in the early twenties, the epiphyseal plate completely ossifies so that only a thin epiphyseal line remains and the bones can no longer grow in length. Bone growth is under the influence of growth hormone from the anterior pituitary gland and sex hormones from the ovaries and testes.

Even though bones stop growing in length in early adulthood, they can continue to increase in thickness or diameter throughout life in response to stress from increased muscle activity or to weight. The increase in diameter is called appositional growth. Osteoblasts in the periosteum form compact bone around the external bone surface. At the same time, osteoclasts in the endosteum break down bone on the internal bone surface, around the medullary cavity. These two processes together increase the diameter of the bone and, at the same time, keep the bone from becoming excessively heavy and bulky.