4.5.3.4 - Hormones in human reproduction

What happens during puberty?

During puberty reproductive hormones cause secondary sex characteristics to develop.

What is the main female hormone?

Oestrogen is the main female reproductive hormone produced in the ovary.

At puberty eggs begin to mature and one is released approximately every 28 days.

This is called ovulation and is involved in the menstrual cycle

What is the main male hormone?

Testosterone is the main male reproductive hormone produced by the testes and it stimulates sperm production.

Describe FSH.

• produced in the pituitary gland

• Causes the maturation of an egg in the ovary ( in a structure called a follicle)

• Stimulates the ovaries to produce oestrogen

Describe osterogen.

• produced by the ovaries

• Cause the lining of the uterus to grow

• Stimulates the release of LH

• Inhibits the release of FSH

Describe LH

• produced in the pituitary gland

• Stimulates the release of an egg at day 14 (otherwise ovulation)

• Stimulates ovaries to produce progesterone

Describe progesterone

• produced in the ovaries

• Maintains the uterus lining during the second half of the menstrual cycle

• Inhibits the production of LH and FSH

Describe the menstrual cycles stages.

Stage 1 - (roughly five, six days) - the uterus lining breaks down (otherwise menstruation)

Stage 2 - (day 5 to day 14) - the lining of the uterus builds up (not a thick spongy layer full go blood vessels

Stage 3 - (day 14) - ovulation - a developed egg is related from the ovary

Stage 4 - (day 14 to day 28) - the lining of the uterus is maintained. If no fertilised egg has landed on the uterus wall by day 28, the cycle starts again