Delayed puberty can be caused by a variety of factors, which broadly fall into three categories: constitutional, systemic/medical, and primary disorders of the reproductive system. Here’s a breakdown:
1. Constitutional Delay (Most Common Cause)
- Also called constitutional delay of growth and puberty (CDGP).
- A normal variant — the child is otherwise healthy but matures later than peers.
- Often runs in families ("late bloomers").
- Puberty eventually proceeds normally without treatment.
2. Chronic Medical Conditions
- Nutritional deficiencies (e.g. malnutrition, anorexia nervosa)
- Chronic illnesses (e.g. cystic fibrosis, celiac disease, inflammatory bowel disease)
- Endocrine disorders (e.g. hypothyroidism, diabetes)
- Chronic kidney or liver disease
3. Hypogonadotropic Hypogonadism
(Problem with the hypothalamus or pituitary gland, leading to low gonadotropins — LH & FSH)
- Congenital (e.g. Kallmann syndrome — associated with loss of smell)
- Acquired (e.g. brain tumors, head trauma, radiation, infections)
4. Hypergonadotropic Hypogonadism
(Problem in the gonads themselves — ovaries or testes — leading to high gonadotropins but low sex steroids)
- Chromosomal abnormalities (e.g. Turner syndrome in girls, Klinefelter syndrome in boys)
- Gonadal dysgenesis or damage (e.g. chemotherapy, radiation, infection, surgery)
5. Other Causes
- Excessive physical training (e.g. in gymnasts, runners)
- Severe psychological stress
- Medications (such as corticosteroids or opioids)
When is it considered delayed?
- Girls: No breast development by age 13 or no menarche (first period) by age 15.
- Boys: No testicular enlargement by age 14.