The Menstrual Cycle

Question 1

What is the menstrual cycle?

Answer 1

The monthly sequence of events in which the female body releases an egg and prepares the uterus in case the egg is fertilised

Question 2

Name the four hormones that control the menstrual cycle.

Answer 2

• Oestrogen
• Progesterone
• LH
• FSH

Question 3

Describe what happens during days 1-5 of the menstrual cycle.

Answer 3

• ‘Menstruation’ occurs - the breakdown of the uterus lining, in the case the fertilised egg has not implanted into the uterus
• There is a high FSH level - FSH causes the maturation of the egg and stimulates oestrogen production in the ovaries

Question 4

Describe what happens during days 6-13 of the menstrual cycle.

Answer 4

• Oestrogen level starts to rise, causing the uterus lining to thicken and build up
• (When oestrogen levels rise, the production of FSH is inhibited to prevent another egg from maturing)
• The oestrogen level reaches its peak

Question 5

Describe what happens on day 14 of the menstrual cycle.

Answer 5

• The high oestrogen level stimulates an LH surge
• This causes ovulation - the release of an egg
• It also stimulates the remains of the follicle to develop into a corpus luteum

Question 6

Describe what happens during days 15-28 of the menstrual cycle.

Answer 6

• The corpus luteum secretes progesterone, which maintains the lining of the uterus
• The high progesterone level inhibits the production of LH
• (If the fertilised egg is not implanted into the uterus, the progesterone level decreases to a point that menstruation can start over, allowing FSH level to increase)

Question 7

Explain what happens to the level of progesterone if a fertilised egg is implanted in the uterus by the end of the menstrual cycle.

Answer 7

The level of progesterone will remain high in order to maintain the lining of the uterus during pregnancy