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Puberty facts

  • Puberty is the period of sexual maturation and achievement of fertility.
  • The time when puberty begins varies greatly among individuals; however, puberty usually occurs in girls between the ages of 10 and 14 and between the ages of 12 and 16 in boys.
  • Body fat and/or body composition may play a role in regulating the onset of puberty.
  • Puberty is associated with development of secondary sex characteristics and rapid growth.
  • Some medical conditions may worsen or first become apparent at puberty.
  • Precocious puberty is puberty that occurs earlier than usual. It is more common in girls than in boys.

What is puberty?

Puberty is the period during which growing boys or girls undergo the process of sexual maturation. Puberty involves a series of physical stages or steps that lead to the achievement of fertility and the development of the so-called secondary sex characteristics, the physical features associated with adult males and females (such as the growth of pubic hair). While puberty involves a series of biological, or physical, transformations, the process can also have an effect on the psychosocial and emotional development of the adolescent.

When does puberty occur?

The onset of puberty varies among individuals. Puberty usually occurs in girls between the ages of 10 and 14, while in boys it generally occurs later, between the ages of 12 and 16. In some African-American girls, puberty begins earlier, at about age 9, meaning that puberty occurs from ages 9 to 14.

Adolescent girls reach puberty today at earlier ages than were ever recorded previously. Nutritional and other environmental influences may be responsible for this change. For example, the average age of the onset of menstrual periods in girls was 15 in 1900. By the 1990s, this average had dropped to 12 and a half years of age.

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Puberty and Girls

Girls and Mood Swings

Because of the surges in hormones during puberty, many girls feel moodiness at times, especially right before their periods. This is called premenstrual syndrome (PMS). PMS may cause:

  • Irritability
  • Difficulty sleeping
  • Fluid retention
  • Anxiety
  • Dietary cravings

Once your period starts, the PMS symptoms usually disappear. It's helpful to exercise during PMS and your period in order to boost your mood and help you feel your best. If your mood is lower than normal, talk to your health care provider about your feelings.

Some girls have a decrease in self-esteem and body satisfaction if they hit puberty earlier than their friends. Other girls feel different if they enter puberty later than their friends do. That's why it's important to understand what's happening in your body, and realize that every girl goes through the same changes -- some sooner, some later. But if you have not gone through puberty by age 14, including menstruating, you should see your primary health care practitioner.

WebMD Medical Reference