There are many possible causes of delayed puberty, some of which affect both genders and some of which are gender-specific. This condition generally refers to the late onset or absence of physiological sexual characteristics that occur during the adolescent years or puberty.

While several factors determine the onset of puberty, failure of sexual development by the ages of 14 and 15 in boys and girls, respectively, is considered a delay in puberty.

The causes are separated into two broad categories: central and peripheral. Central causes may affect both genders and stem from the hypothalamic-pituitary axis or other areas of the body that are not specific to a gender. Peripheral causes, on the other hand, are  gender specific and linked to the sexual organs of the individual.

The most common cause in both boys and girls is constitutional delay. However, a diagnosis of constitutional delay can only be made when other possible causes have been excluded.

Central Causes (Males and Females)

Many central causes are related to impaired structure or function of the hypothalamic-pituitary axis. This may result from:

• Growth of a tumor near the hypothalamic-pituitary axis (e.g. astrocytoma, craniopharyngioma, germinomas, optic glioma, pituitary tumor)
• Physical trauma to the head (e.g. injury or surgery)
• Radiation therapy directed towards the hypothalamic-pituitary axis
• Congenital abnormality of the hypothalamic-pituitary axis
• Abnormal hormone levels (e.g. low gonadotropin and sex steroid concentration)

There are also several central causes that are not associated with abnormal structure and function of the hypothalamic-pituitary axis. These include:

• Health conditions (e.g. kidney disease, Crohn’s disease, cystic fibrosis, hypothyroidism)
• Medications (e.g. steroid therapy)
• Malnutrition (e.g. coeliac disease, anorexia nervosa)
• Excessive physical exertion (e.g. professional athletes and gymnasts)
• Psychosocial deprivation

Peripheral Causes (Males)

Peripheral causes that may lead to delayed puberty in boys include:

• Testicular damage to both sides (e.g. cryptorchidism, unsuccessful orchidopexy, atresia, testicular torsion, mumps or other infections)
• Health conditions (e.g. Noonan’s syndrome, Prader-Willi syndrome, Bardet-Beidl syndrome, Klinefelter’s syndrome, chromosomal disorders)
• Radiation therapy directed to the testicular or genital region
• Medications (e.g. cyclophosphamide)

Peripheral Causes (Females)

Peripheral causes that may lead to delayed puberty in girls include:

• Health conditions (e.g. Turner syndrome, Prader-Willi, Bardet-Biedl syndrome, Swyer syndrome, polycystic ovary syndrome)
• Medications (e.g. cyclophosphamide, busulfan)
• Radiation therapy directed to the abdominal region
• Sexual disorders (e.g. androgen insensitivity syndrome, congenital adrenal hyperplasia)
• Thalassaemia (overload of iron)

Determining the Cause

It is important to establish the cause of delayed puberty in affected individuals, as it provides valuable information about the most appropriate therapy options.

During the diagnostic process, it is important to discuss the family and medical history of the patient, with specific questions to uncover individuals at risk of associated health conditions or other causes. Blood tests to check the levels of hormones in the blood can be useful to detect any abnormalities that may be causing the pubertal delay. In some cases, other diagnostic tests such as ultrasound or magnetic resonance imaging (MRI) may also be recommended.

References

• http://patient.info/doctor/delayed-puberty
• http://www.hormone.org/questions-and-answers/2013/delayed-puberty
• http://www.merckmanuals.com/professional/pediatrics/endocrine-disorders-in-children/delayed-puberty
• http://www.bsped.org.uk/patients/docs/delayed_puberty_tr_version.pdf