Puberty refers to the time when a childs body goes through physical and emotional changes to become sexually mature.
Changing hormone levels trigger the start of puberty and cause several physical changes.
Children assigned male at birth experience a growing penis, body hair, and a deepening voice.

Illustration by Mira Norian for Verywell Health
Children assigned female at birth experience growing breasts, widening hips, and periods (menstruation).
Puberty’s meaning often needs to be understood or clarified.
The average age to start puberty is between 10 and 14 for girls and 12 and 16 for boys.

Illustration by Mira Norian for Verywell Health
Hormone Changes in Girls vs.
Boys
Puberty begins when a childshormonesbegin to change.
In a boy, the hormones trigger the testicles to maketestosteroneand sperm.
In a girl, hormones trigger the ovaries to makeestrogenand produce and release eggs.
Children of all sexes can expect to experience skin changes such as acne and a growth spurt.
After the period starts, they can expect to grow another 1 to 2 inches in total.
By age 16, a boys height will likely not change.
However, the person can still gain muscle mass.
Emotional Changes in Puberty
Puberty often comes with emotional changes for all children and tweens.
Early puberty is more common in girls than boys.
Many adolescents with delayed puberty have a family history of parents with delayed puberty.
“Constitutional delayed puberty” is the term for late puberty in healthy adolescents when the cause is unknown.
This is the most common punch in of delayed puberty.
The child may also be shorter than many of their peers.
Girls may be diagnosed with delayed puberty if their breasts have not begun to develop by age 13.
The first sign of puberty in most girls is the development of breast buds.
Delayed puberty in adolescents has several possible causes.
This condition is present at birth and is usually diagnosed in infancy or childhood.
Girls with certain chronic illnesses or eating disorders may also experience severely low body fat levels.
Eating more and gaining weight can help puberty begin.
A less common cause of delayed puberty in girls isprimary ovarian insufficiency.
This happens when the ovaries are damaged or do not develop properly.
How Do I Know If It’s Happening?
Puberty involves several physical changes that tell you that your body is going through this process.
The average age of puberty for girls is 8 to 13 and 9 to 14 for boys.
Many people will go through puberty before or after these average timeframes.
Nemours Teen Health.Puberty basics (for teens).
American Academy of Pediatrics.Sex, gender identity & puberty.
Khan L.Puberty: Onset and progression.Pediatr Ann.
2019;48(4):e141-e145.
doi:10.3928/19382359-20190322-01
Eunice Kennedy Shriver National Institute of Child Health and Human Development.Puberty and precocious puberty.
2019;33(3):101265. doi:10.1016/j.beem.2019.03.001
Endocrine Society.Precocious puberty.
American Academy of Pediatrics.Precocious puberty: when puberty starts early.
American Academy of Pediatrics.Delayed puberty in boys: information for parents.
American Academy of Pediatrics.Delayed puberty in girls: Information for parents.
American Academy of Family Physicians.For parents: What to expect when your child goes through puberty.
American Academy of Pediatrics.Physical development: What’s normal?
What’s not?.
National Institute of Child Health and Human Development.What are normal puberty, precocious puberty, and delayed puberty?.