Sexual Development of

Girls & Boys

The female hormone is called Oestrogen (ees-tro-jan) and Progesterone (pro-jest-a-rone)

These are true names and the main cause of periods.There are more sex hormones, most can be found in

your saliva but... Oestrogen and Progesterone are the main two for women. 

The male hormone is testosterone

Sexual Development of Girls

Girls usually start to show the physical changes of puberty between the ages of 9 and 13, which is slightly sooner than boys. The female sex hormone called

estrogen and other hormones cause the physical changes. Many girls are fully

developed by the age of 16. Some girls will continue to develop through age 18.

Stage 1:

Between ages 8 to 12 .No visible signs of physical

development. But the ovaries are enlarging and

hormone production is beginning.

Stage 2:

May begin anywhere from ages 8 to 14.Height and weight increase rapidly.Fine hair growth begins close to the

pubic area and underarms.Breast buds appear; nipples become raised and this area may be tender.Sweat and oil glands become more

active which can result in acne.

Stage 3:

May begin anywhere from ages 9 to 15.Breasts become rounder and fuller.

Hips may start to widen in relation to waist.Vagina begins secreting a clear or whitish

fluid.Pubic hair becomes darker, thicker, and curlier.

Height and weight continue to increase.For some girls, ovulation and menstruation

 (periods) begin, but may be irregular.

Stage 4:

May begin anywhere from ages 10 to 16.Underarm hair becomes darker.

Pubic hair starts to form a triangular patch in front and around sides of genital area.

The nipple and the dark area around the breast (areola) may stick out from the rest of

the breast.For many girls, ovulation and menstruation

(periods) begin, but may be irregular.

Stage 5:

May begin anywhere from ages 12 to 19.Adult height is probably

reached.Breast development is complete.

Pubic hair forms a thick, curly, triangular patch.

Ovulation and menstruation (periods) usually occur regularly.

Overall look is that of a young adult woman.

Sexual Development of Boys

Stage 1:

May begin as early as age 9 and continue until 14.No sign of physical

development but hormone production is beginning.

Stage 2:

May begin anywhere from ages 11 to 13.Height and weight increase

rapidly.Testicles become larger and

scrotum hangs lower.Scrotum becomes darker in color.

Fine hair growth begins at the base of the penis.

Hair growth may begin on the legs and underarms.

Stage 3:

May begin anywhere from ages 12 to 14.The penis, scrotum, and testicles grow.

Pubic hair becomes darker, thicker, and curlier.Muscles become larger and shoulders become

broader.Sweat and oil glands become more active,

which can result in acne.Sperm production may begin.

Temporary swelling and tenderness may occur around nipples.

Height and weight continue to increase.Hair growth on the legs and underarms

continues.

Stage 4:

May begin anywhere from ages 13 to 16.

Sperm production has usually begun.

The larynx (Adam's apple) increases in size. Vocal chords become longer and thicker, and the voice begins to break or crack, then becomes low.

Height and weight continue to increase.

Penis and testicles continue to grow.Pubic hair increases in amount and becomes darker, coarser, and curly.

Stage 5:

May begin anywhere from ages 14 to 18.Growth of facial hair begins.

Chest hair growth may begin (not all males get much chest hair).

Adult height is reached.Penis and testicles have reached full adult

size.Pubic, underarm, and leg hair are adult color,

texture, and distribution.Overall look is that of a young adult man.

Thanks