In the United States, which of the following is a common influence on a childs height

Topic Resources

For height and weight charts for children 2 years of age and older, see growth charts from the Centers for Disease Control and Prevention (CDC).

There is a growth spurt during adolescence. The growth spurt in boys occurs during mid-adolescence between the ages of about 12 years and 16 years (most commonly about age 13½) and usually begins a year after the testes start enlarging. Boys grow about 4 inches (about 10 centimeters) during their year of maximum growth. The growth spurt in girls occurs in early adolescence between the ages of about 9½ years and 13½ years (most commonly about age 11½). Girls grow about 3½ inches (about 9 centimeters) during their year of maximum growth. In general, boys become heavier and taller than girls.

Sexual maturation or puberty begins at different ages depending on genetic and environmental factors. Sexual maturity begins earlier today than a century ago, probably because of improvements in nutrition, general health, and living conditions. For example, the average age that girls begin menstruating has decreased by about 3 years over the past 100 years. However, whenever sexual maturation begins, it typically occurs in the same order.

In both boys and girls, pubic and/or axillary hair may appear first. This appearance may be a normal variation but should be discussed with a doctor.

Milestones in Sexual Development

The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

• Growth charts from the Centers for Disease Control and Prevention (CDC) for children age 2 years and older in the United States

CLICK HERE FOR THE PROFESSIONAL VERSION

Topic Resources

During the preschool and school years, growth in height and weight is steady. Children tend to grow a similar amount each year until the next major growth spurt occurs in early adolescence.

Children who are beginning to walk have an endearing physique, with the belly sticking forward and the back curved. They may also appear to be quite bow-legged. By 3 years of age, muscle tone increases and the proportion of body fat decreases, so the body begins to look leaner and more muscular. Most children are physically able to control their bowels and bladder at this time.

Doctors report how children are growing in relation to other children their age and monitor the children's weight gain compared to their height. From birth until 2 years of age, doctors record all growth parameters in a chart by using standard growth charts from the World Health Organization (WHO). After age 2, doctors record growth parameters by using growth charts from the Centers for Disease Control and Prevention (CDC).

Length in children who are too young to stand is measured while children lie on their back on a suitable device, such as a measuring table (called a stadiometer). Height in children who can stand is measured using a vertical measuring scale. In general, length in normal-term infants increases about 30% by age 5 months and more than 50% by age 12 months. Infants typically grow about 10 inches (25 centimeters) during the first year, and height at 5 years is about double the birth length. In boys, half the adult height is attained by about age 2. In girls, height at 19 months is about half the adult height.

Weight and Length Charts for Infants from Birth to 24 Months of Age

During the first year of life, an infant's weight and length are charted at each doctor's visit to make sure that growth is proceeding at a steady rate. Percentiles are a way of comparing infants of the same age. For an infant at the 10th percentile for weight, 10% of infants weigh less and 90% weigh more. For an infant at the 90th percentile, 90% of infants weigh less and 10% weigh more. For an infant at the 50th percentile, 50% of infants weigh less and 50% weigh more. Of more significance than the actual percentile is any significant change in percentile between doctor's visits. (Adapted from WHO Child Growth Standards. Available at www.cdc.gov/growthcharts.)

Height and Weight Charts for Boys and Girls 2 to 10 Years of Age

Adapted from The National Center for Health Statistics in collaboration with the National Center for Chronic Disease Prevention and Health Promotion (2000). Available at www.cdc.gov/growthcharts.

Head circumference is measurement around the largest area of a child's head. Doctors place the tape measure above the eyebrows and ears and around the back of the head. This measurement is important because the size of the head reflects the size of the brain, and this measurement lets doctors know whether the child's brain is growing at a normal rate. Head circumference is routinely measured until children are 3 years old.

At birth, the brain is 25% of its future adult size, and head circumference is about 14 inches (about 35 centimeters). By 1 year of age, the brain is 75% of its adult size. By 3 years of age, the brain is 80% of its adult size. By 7 years of age, the brain is 90% of its adult size.

Lower front teeth usually begin to appear by the age of 5 to 9 months. Upper front teeth usually begin to appear by 8 to 12 months. On average, infants have 6 teeth by age 12 months, 12 teeth by 18 months, 16 teeth by 2 years, and all 20 of their baby (deciduous) teeth by 2½ years. Baby teeth are replaced by permanent (adult) teeth between the ages of 5 years and 13 years. Permanent teeth tend to appear earlier in girls.

The following are English-language resources that may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

• Growth charts from the World Health Organization (WHO) for infants and children ages 0 to 2 years of age in the United States

• Growth charts from the Centers for Disease Control and Prevention (CDC) for children age 2 years and older in the United States

CLICK HERE FOR THE PROFESSIONAL VERSION