Girls' Puberty: Stages, Signs, and What to Expect

In short: Puberty in girls usually starts between 8 and 10 years and lasts about 4 years. The signs appear in order: breast growth, then pubic and underarm hair, then the growth spurt, then periods 2–3 years after breast growth, at about 12–13. Weight, nutrition and heredity affect the timing. Ask the doctor if signs appear very early or are much delayed.

Puberty is the natural process in which a girl’s body gradually develops the physical features of adulthood — such as breast development, pubic hair, and the ability to become pregnant. Understanding what to expect can help both girls and parents feel more confident during this stage of growth.

Puberty usually begins in girls between the ages of 8 and 13 years (on average around 10 to 11) and continues for about 4 years.

Puberty depends on several factors, the most important of which are:

• Weight: Puberty tends to begin earlier in girls who are overweight

• Nutrition: Girls who are underweight or who do not receive proper nutrition — or who have trouble absorbing nutrients — often begin puberty later

• Genetics: If a mother reached puberty early, her daughter is likely to as well

• Ethnic background: on average, girls of African descent begin puberty somewhat earlier (up to about a year) than girls of European descent

How does the growth happen?

Puberty is guided by hormones — chemical messengers made in certain parts of the body and carried through the bloodstream to signal changes elsewhere. In girls, puberty begins when hormones released by the brain signal the ovaries to grow. The ovaries then release estrogen, which supports the growth of the reproductive system, including:

• Breasts

• The vagina

• Ovaries

• The uterus

The order of pubertal changes is as follows:

• First, breast development begins — typically between the ages of 8 and 13 years

• Shortly after, hair begins to grow in the armpits and genital area

• A growth spurt in height follows, and growth slows once the menstrual cycle begins

• The first period usually comes about 2 to 3 years after breast development starts

• The first period usually happens around age 12 or 13. A period starting before about age 10 is early and should be checked by a doctor. It can normally occur anytime between the ages of 10 and 15. Cycles are usually irregular at first and may take up to five years to become regular.

A girl should be seen by a doctor if she has no breast development by age 13, no period by age 15, or no period within 3 years of breast development starting.

• Growth in height usually stops in girls between the ages of 14 and 16 years

As girls go through puberty, their body shape naturally changes — hips and thighs widen, and body fat increases. This is a completely normal part of female development.

Some girls may experience hormonal variations, such as delayed puberty or early (precocious) puberty. If you’re ever concerned about the timing or pattern of your daughter’s development, it can help to speak with a specialist for personalized guidance.

Frequently Asked Questions:

Q: What happens when a girl reaches puberty?

Puberty progresses through several stages, beginning with physical changes such as increased body fat, breast growth, increased height and weight, and sometimes acne. About 2 to 3 years after the first signs of puberty (breast development) appear, the first period usually begins.

Q: Do girls grow taller after puberty?

Most of a girl’s growth spurt happens in the first two to three years of puberty, when she may grow about 6 to 9 centimeters a year; after her first period she usually gains only about 5 to 7.5 centimeters more. Growth generally stops for most girls around the age of 14 or 15, though this can vary depending on when her first period occurred. It’s worth noting that a girl’s final height is closely linked to genetics from both parents, and often tends to resemble the mother’s height.

Q: What are the risks of early puberty for girls?

One of the main concerns is shorter adult height. Children with early (precocious) puberty may initially grow faster and appear taller than peers their age, but their bones mature prematurely — meaning their growth stops earlier than it otherwise would.

Q: Does a girl’s height increase after her first period?

Most girls gain an additional 5 to 7.5 cm in height within a year or two after their first period.

Age and Average height in cm

At the age of 17 years, height ranges between (150-175) cm

At the age of 18 years, height ranges between (151-175) cm

At the age of 19 years, height ranges between (151-175) cm

Q: When does a girl reach puberty after pubic hair appears?

Usually within one to two years

Q: When does the first period come after breast development appears?

Usually within two to three years

Q: When does puberty begin in girls?

Typically between the ages of 8 and 13, usually starting with breast development

Q: When does armpit hair begin to appear in girls?

Armpit hair usually appears around the age of 12 to 13, after breast development and pubic hair have started. Pubic or armpit hair before age 8 should be checked by a doctor

Q: Does vitamin D increase height after puberty?

There is currently no research confirming this

Q: When does puberty end?

Typically around the age of 16 to 17 years.

If you have questions about your daughter’s growth and development, or would like guidance from an experienced specialist, the team at Dr. Najeeb Layyous’s clinic is here to help.

Dr Najeeb Layyous F.R.C.O.G

Consultant Obstetrician, Gynecologist and Infertility Specialist