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Delayed Puberty


Andrew Calabria

, MD, Perelman School of Medicine at The University of Pennsylvania

Last full review/revision Sep 2020| Content last modified Sep 2020

Delayed puberty is defined as absence of the start of sexual maturation at the expected time.

  • Most often, children simply develop later than their peers but ultimately develop normally.
  • Sometimes, delayed puberty is caused by chronic medical problems, hormonal disorders, radiation therapy or chemotherapy, disordered eating or excessive exercise, genetic disorders, tumors, and certain infections.
  • Typical symptoms include a lack of testicular enlargement in boys and a lack of breasts and menstrual periods in girls.
  • The diagnosis is based on the results of a physical examination, various laboratory tests, a bone age x-ray, and, if needed, genetic testing and magnetic resonance imaging.
  • Treatment depends on the cause and may include hormone replacement therapy.

(See also Puberty in Boys and Puberty in Girls.)

The start of sexual maturation (puberty) takes place when the hypothalamus gland begins to secrete a chemical signal called gonadotropin-releasing hormone. The pituitary gland responds to this signal by releasing hormones called gonadotropins, which stimulate the growth of the sex glands (the testes in boys and the ovaries in girls). The growing sex glands secrete the sex hormones testosterone in boys and estrogen in girls. These hormones cause the development of secondary sex characteristics, including facial hair and muscle mass in boys, breasts in girls, and pubic and underarm hair and sexual desire (libido) in both sexes.

Some adolescents do not start their sexual development at the usual age.

In boys, delayed puberty is more common and is defined as

  • No enlargement of the testes (testicles) by age 14
  • A time lapse of more than 5 years from the start to the completion of growth of the genitals

In girls, delayed puberty is defined as

  • No breast development by age 13
  • A time lapse of more than 3 years from the beginning of breast growth to the first menstrual period
  • No menstruation (amenorrhea) by age 16

Causes of Delayed Puberty

In the majority of cases, delayed puberty represents a normal variation, which may run in the family (also called constitutional delay of puberty). These adolescents, sometimes referred to as "late bloomers," have a normal growth rate and are otherwise healthy. Although the growth spurt and puberty are delayed, they eventually proceed normally.

Various disorders, such as poorly controlled diabetes mellitus, inflammatory bowel disease, kidney disease, cystic fibrosis, and anemia, can delay or prevent sexual development. Development may be delayed or absent in adolescents receiving radiation therapy or cancer chemotherapy. Puberty may also be delayed by autoimmune disorders (such as Hashimoto thyroiditis, Addison disease, and some disorders that directly affect the ovaries). A tumor that damages the pituitary gland or the hypothalamus can lower the levels of gonadotropins or stop production of the hormones altogether.

In boys, testicular disorders such as injury, for example, resulting from prior twisting of a testis (testicular torsion), or infection (such as mumps) may delay puberty. Adolescents, particularly girls, who become very thin because of excessive exercise or dieting often have delayed puberty, including an absence of menstruation (amenorrhea).

Chromosomal abnormalities, such as Turner syndrome in girls and Klinefelter syndrome in boys, and other genetic disorders can affect the production of sex hormones. One of these genetic disorders, Kallmann syndrome, affects only gonadotropin production (without affecting production of other hormones).

Symptoms of Delayed Puberty

Adolescents who have delayed puberty may be noticeably shorter than their peers, can be teased or bullied, and often need help coping with and managing social concerns. Although adolescents are typically uncomfortable about being different from their peers, boys in particular are more likely to feel psychologic stress and embarrassment resulting from delayed puberty.

Diagnosis of Delayed Puberty

  • A physical examination
  • Bone age x-ray
  • Blood tests
  • Sometimes magnetic resonance imaging

The initial evaluation of delayed puberty should consist of a complete history and physical examination to evaluate pubertal development, nutritional status, and growth.

Doctors often take x-rays of one or more bones to see the level of bone maturity (called a bone age x-ray).

Doctors take blood samples and do basic laboratory tests to look for signs of chronic disease, hormone level tests, and possibly genetic testing.

Doctors usually evaluate boys who have no signs of puberty by age 14 years and girls who have no signs of puberty by age 13 years or who have not menstruated by age 16 years. If these children otherwise appear healthy, they most likely have constitutional delay. The doctor may decide to re-examine these adolescents at 6-month intervals to ensure that puberty begins and progresses normally.

Girls with severely delayed puberty should be evaluated for primary amenorrhea.

Magnetic resonance imaging (MRI) may be done to ensure that there is no brain tumor or structural abnormality in the pituitary gland.

Treatment of Delayed Puberty

  • Treatment of cause
  • Hormone therapy

The treatment for delayed puberty depends on its cause. When an underlying disorder is the cause of delayed puberty, puberty usually proceeds once the disorder has been treated.

An adolescent who is naturally late in developing needs no treatment, but if the adolescent is severely stressed by delayed or absent development, some doctors may give supplemental sex hormones to begin the process sooner. This treatment is much more common among boys. Children with delayed puberty often need additional support from parents, family members, and friends to ensure they have a healthy body image and self-esteem.

If boys show no sign of puberty by age 14, they may be given a 4- to 6-month course of testosterone injections once a month. At low doses, testosterone starts puberty, causes the development of some masculine characteristics (virilization), and does not prevent adolescents from reaching their adult height potential.

In girls, low doses of estrogen may be started with pills or skin patches.

Genetic disorders cannot be cured, but hormone therapy may help sex characteristics develop.

Surgery may be needed to remove pituitary tumors, and these children are then at risk of hypopituitarism (a deficiency of one or more pituitary hormones).

Drugs Mentioned In This Article

Generic Name Select Brand Names
testosterone DELATESTRYL

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