Growth and development, ages 11 to 14: What to expect

Posted: Updated:

PHOENIX -- Each adolescent develops at his or her individual pace, general growth and development patterns can be grouped into four main categories.

Physical development – Growth spurts occur during the adolescent years (starting at about age 11 in girls and at about age 13 in boys). This rapid growth usually precedes or accompanies puberty.

Cognitive development – This is the process by which the brain develops the abilities to think, learn, reason, and remember.

Emotional and social development – In trying to establish their individuality, adolescents typically distance themselves from parents and prefer being with friends, handing out in their rooms, or listening to music. Include them in family events even If you meet with resistance.

Sensory and motor development – Adolescents may be somewhat awkward or clumsy. To help improve coordination and establish healthy habits. Puberty’s changes start when the brain triggers the production of sex hormones.

For most girls, puberty begins around age 11. For boys, puberty starts from 10 to 14. The average age is 12.

Breast growth is usually the first sign of puberty girls will notice. First, small lumps form behind the nipples.

The first sign of puberty in boys is subtle – an increase in testicle size.

After breasts and testicles start growing, body hair will start to grow in and become thicker. For both boys and girls, new hair will start growing in the armpits and pubic area around the genitals. Boys also may start developing chest and facial hair.

Mild acne may be normal in early puberty.

About a year after puberty begins, girls have a growth spurt. A girl will get taller and start to get wider hips and fuller breasts.

A girl usually gets her first period between 10 and 16 years old.

Toward the end of puberty, your son’s voice may start cracking. This is normal, and will stop after a few months. When it does, his voice will sound deeper. Voice changes are caused by testosterone.

Discovering that your child is entering puberty early can be alarming. Many kids who have early puberty don’t need treatment. In those who do, treatment usually works well in halting development.

Puberty starts on average in girls between ages 8 and 13 and boys between ages 9 and14.

Girls who show significant signs of puberty and its progression before age 7 and boys before age 9 are considered precocious.

The pituitary glands are prompted to produce hormones, called gonadotropins. These hormones in turn stimulate the testicles or ovaries to make other hormones, testosterone or estrogen. It’s these sex hormones that cause the changes of puberty, like breast development in girls.

Researchers have found signs of puberty in American boys up to two years earlier – age 9 on average for blacks, 10 for whites and Hispanics. Other studies that girls, too, are entering puberty younger.

Why is this happening? Higher levels of obesity and inactivity, chemicals in food and water, all of which might interfere with normal hormone production. Earlier puberty is not necessarily cause for concern.

Strong physical evidence that boys are maturing earlier.

Doctors generally consider puberty early if it begins before age 8 in girls.

Boys are more likely than girls to have an underlying physical cause for early puberty.

In girls, early puberty has been linked with increased chances for developing breast cancer. Whether it poses health risks for boys is uncertain. Some scientists think early puberty may increase the risk for testicular cancer.


Dr. Art Mollen's practice is located at 16100 N. 71st St. in Scottsdale. For more information, call 480-656-0016 or log on to