Menstruation
Biology: AQA GCSE Higher, topic 5.3.20
The Menstrual Cycle
The menstrual cycle is a monthly cycle, which involves the maturation (process of maturing) and release of an egg. If sexual intercourse has occurred, this can result in pregnancy.
Key hormones
- The menstrual cycle is controlled by four hormones from the endocrine system:
- Follicle Stimulating Hormone (FSH)
- Oestrogen
- Luteinising Hormone (LH)
- Progesterone
Stages
- The menstrual cycle can be divided into four stages depending on the levels of the hormones.
Eggs
- A female is born with all of her eggs ready, but only one egg will mature each month once the female reaches puberty.
Test yourself on Menstruation
A female's last menstrual cycle began four weeks ago. Is she likely to start her next cycle soon?
A couple have sexual intercourse shortly after the woman's egg has matured and been released. Could this result in pregnancy?
Which of the following are true of the menstrual cycle?
A female has already released several eggs over multiple menstrual cycles since reaching puberty. Where did these eggs originally come from?
A female's period is now eight weeks overdue, with no period in between. Based on how often the menstrual cycle usually repeats, what does this suggest?