Puberty and the Menstrual Cycle

Hormones

• At puberty, your body starts to release sex hormones that trigger secondary sexual characteristics and cause eggs to mature in women.
• In men, the main reproductive hormone is testosterone, which is produced by the testes and stimulates sperm production.
• In women, the main reproductive hormone is oestrogen, which is produced by the ovaries, brings about physical changes and is involved in the menstrual cycle.

The menstrual cycle

• During stage 1, menstruation starts, causing the uteral lining to break down. This happens for about 4 days.
• During stage 2, the uteral lining builds up again, from day 4 to 14, into a thick spongy layer full of blood vessels, ready to receive a fertilised egg.
• During stage 3, an egg…