Puberty is marked by physical changes such as pubic hair, breast development in girls and testicular development and penile enlargement in boys. Boys start puberty within a wide range of ages but most start between the ages of 9 and 14. Girls typically develop signs of puberty between the ages of 7 or 8 and 13.
In boys, delayed puberty is when puberty has not started by age 14. In girls, delayed puberty is when breast development has not started by age 13.
The most common form of delayed puberty in boys is constitutional delay of puberty. This means that the child is otherwise healthy, but puberty simply has not yet occurred. While more common in boys, girls may also experience constitutional delay of puberty. In boys and girls, this may be inherited from one or both parents. Constitutional delay of puberty typically resolves with time.
In a smaller number of boys, delayed puberty is caused by a condition called isolated hypogonadotropic hypogonadism (iHH), or isolated gonadotropin deficiency (IGD). This is a lifelong condition in which there is a deficiency of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). These hormones are produced in the pituitary gland and control the function of the gonads (testes in males and ovaries in females). Other pituitary hormones in this condition are made normally, and usually growth is normal. Isolated gonadotropin deficiency is typically present at birth. Many boys with iHH are born with a penis that is smaller than normal. Other signs of iHH include:
- Failure to start puberty by age 17
- Poor sense of smell (a condition called Kallmann syndrome that affects some boys with iHH)
- Very small testicles or testicles that cannot be readily felt
In girls, delayed puberty may be caused by having low body fat. Low body fat may be found in girls who:
- Are extremely athletic (especially competitive swimmers, ballet dancers and gymnasts)
- Practice extreme dieting or have an eating disorder such as anorexia or bulimia
- Have a chronic condition that inhibits growth such as cystic fibrosis or chronic kidney disease
Other causes of delayed puberty in girls include:
- Primary ovarian insufficiency. With primary ovarian insufficiency, the ovaries either do not develop properly or are damaged. Primary ovarian insufficiency may be caused by:
- Turner syndrome. Turner syndrome is a congenital condition (present at birth) in which one of the two X chromosomes is missing. Most girls with Turner syndrome are very short for their age and may have distinctive physical features like webbing of the neck, a high-arched palate or arms that bend outward when extended. Turner syndrome is usually diagnosed well before age 13 because of short stature.
- Radiation therapy and some chemotherapy. The ovaries may become damaged after radiation treatment or some kinds of chemotherapy for cancer.
- Autoimmune condition. Occasionally, the ovaries may be damaged by an autoimmune condition that causes the immune system to attack the ovarian tissue.
- Hormone deficiencies. Some girls fail to start puberty because of a lack of two pituitary hormones—luteinizing hormone (LH) and follicle-stimulating hormone (FSH) (also called gonadotropins). This can occur when there are other pituitary deficiencies, including growth hormone deficiency, or it can be an isolated finding.
Diagnosis of Delayed Puberty
Your child's doctor at Riley at IU Health may perform the following exams and tests to diagnose delayed puberty:
- Physical exam. A physical exam is required to diagnose delayed puberty in both boys and girls. For girls, a pelvic exam is not required.
- Blood test. Your child's doctor may order a blood test to check the level of certain hormones. Low levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol (in girls) and testosterone (in boys) may indicate that a hormonal deficiency is causing delayed puberty. High levels of LH and FSH indicate that primary ovarian or testicular insufficiency is causing delayed puberty.
Treatment for delayed puberty includes:
- Testosterone therapy for boys. In some cases, a doctor may prescribe a few monthly testosterone injections to stimulate puberty in boys. Testosterone is also the treatment for boys with isolated gonadotropin deficiency or testicular problems; testosterone treatment for these conditions must continue for life.
- Estrogen therapy for girls. In some cases, a doctor may prescribe estrogen for several months to stimulate puberty. Girls with primary ovarian insufficiency or a permanent deficiency of gonadotropins will require long-term estrogen replacement therapy. Estrogen can be delivered via a daily tablet or as a patch applied to the skin twice a week. After one to two years of estrogen, doctors typically start a second hormone called progestin. Menstruation should occur a few months after taking this hormone.
- Nutrition. Girls with low body fat may be able to stimulate puberty by eating more calories and gaining weight.
Not all cases of delayed puberty require treatment. Speak with your teen's doctor to learn more about your child's specific case.
Key Points to Remember
Key Points to Remember
- In boys, delayed puberty is when puberty has not started by age 14. In girls, delayed puberty is when breast development has not started by age 13.
- Constitutional delay of puberty in boys and girls may be inherited from one or both parents.
- Constitutional delay of puberty typically resolves with time. However, a doctor may prescribe a period of treatment with testosterone for boys or estrogen for girls to stimulate puberty.
- When girls have delayed puberty due to low body fat, eating more and gaining weight may cause puberty to start.
- If delayed puberty is caused by a gonadotropin deficiency, hormone treatment is required for life (testosterone for males and estrogen and progestin for females).
Support Services & Resources
Support Services & Resources
Visit the links below to learn more about delayed puberty in boys and girls.
Riley at IU Health offers a broad range of supportive services to make life better for families who choose us for their children's care.
The Pediatric Endocrine Society provides detailed information about delayed puberty in girls and boys.