Puberty takes place over a number of years, and the age at which it starts and ends varies widely. It begins somewhere between the ages of 7 and 13 for girls, and somewhere between the ages of 9 and 15 for boys, although it can be earlier or later for some people.

Sometimes, teens pass this normal age range for puberty without showing any signs of body changes. This is called delayed puberty.

  Causes:
There are several reasons why puberty may be delayed. Most often, it's simply a pattern of growth and development in a family; a boy or girl may find someone in the family or relatives might have developed later than usual which is called constitutional delay. It does not require any kind of treatment as it eventually develops normally later. Malnourishment is another reason for delayed puberty.

Medical problems can also cause delays in puberty, Chronic illnesses like diabetes, cystic fibrosis, kidney disease, or even asthma. Problems in the pituitary or thyroid glands, which produce hormones important for body growth and development, slow down the development in individuals. This is where proper treatment and control is required.

Consult your pediatric endocrinologist (pronounced: en-doe-krih-nah-luh-jist), who may ask you to go through some tests, examinations and treat them.

Delayed puberty is not any sickness and it can be solved. But many children will feel embarrassed that they suffer from delayed puberty, especially in boys as they see their own friends develop and grow but no changes happening to them. Other boys may tease them. When you feel depressed or having school or emotional problems related to delays in your growth and development, ask your mom or dad, your doctor, or another trusted adult to find a counselor or therapist whom you can talk to. This person can help you sort out your feelings and suggest ways to cope with them.

Gynecomastia is a condition in which breast tissue forms in guys, usually due to normal hormonal changes during puberty. This is a temporary condition, and it's very unusual for the breasts to stay developed - they will eventually flatten out completely within a few months to a couple of years. It usually goes away on its own and no medical treatment or surgery is needed.

Hormones (androgens) are chemicals produced by your body's glands. Androgens are found in boys. The hormones produced in the testicles are responsible for the physical changes after puberty - facial hair, muscle development, a deepening of the voice etc.

Estrogen is found in girls, sometimes it is produce in few boys too this is where they notice some breast tissue develop. This can appears in boys on one or both sides. This is just a minor change in your hormones as you begin to grow into adulthood and one should not be worried that they are turning into a girl.

Pseudogynecomastia (or false gynecomastia) has nothing to do with puberty or hormones. This is due to the fact that some guys have extra fat in the chest area, making it look like they have breasts.

Although the most common cause of gynecomastia is puberty, certain diseases or side effects of some medications can sometimes cause it. Using illegal drugs such as anabolic steroids, marijuana, or heroin can also disrupt hormonal balance and lead to gynecomastia. A doctor's exam can tell whether a guy has gynecomastia or pseudogynecomastia. But remember that gynecomastia, is temporary breast tissue growth in guys and is a common part of puberty that will usually go away on its own.