Background notes


Puberty: Menstrual cycle



The menstrual cycle is a series of changes a female's body goes through in preparation for possible pregnancy.

Blood, fluid and endometrial tissue build up in the lining of the uterus as the body prepares itself every month to receive a fertilised ovum (egg). If fertilisation doesn't occur, the body discharges the uterus lining in a process known as menstruation, and the cycle starts again.

During the build-up part of the menstrual cycle, the uterus wall becomes soft and spongy to make an ideal settling place for the fertilised ovum. If an ovum is not fertilised it continues down the fallopian tube and passes through the uterus, down the vagina to the outside of the body. The lining of the uterus is no longer needed so the uterus eventually contracts, crumbles and it breaks away forcing the 'debris' down the vagina to the outside.

The menstrual cycle is different for every woman and can vary greatly in the following ways:

  • age of onset and cessation

  • amount of blood loss

  • duration of flow

  • amount of discomfort

  • length of cycle

  • mood change

  • physical symptoms

Menstruation continues until menopause, usually between 45 and 55 years of age.

A doctor should be consulted if:

  • a girl's periods have not started by 16 years of age

  • bleeding occurs between periods

  • periods are very heavy or blood clots are passed

  • the period lasts longer than 8 days

  • despite personal cleanliness there remains a persistent unpleasant odour

Managing menstruation

The two main sanitary choices are tampons and sanitary pads.

Sanitary pads

  • sanitary pads are worn outside the body

  • when blood comes in contact with air, an unpleasant odour may develop. Daily showers, clean briefs and frequent changing of the pad should prevent this. The use of vaginal deodorant should be discouraged as chemical sprays can disturb the delicate dermatological balance of the very sensitive vulva

  • pads should not be flushed down the toilet

  • pads are good for wearing at night or on light days

  • reusable felt pads are an environmentally friendly option


  • tampons are made of tightly packed absorbent material which absorbs the blood flow in the vagina

  • if inserted correctly they can't be felt or fall out

  • they are convenient to use, inconspicuous and very effective

  • they should be changed often and inserted carefully

  • heavy menstrual flow may require a sanitary pad in addition to the tampon

  • tampons should not be flushed down the toilet

  • a reusable silicone cup is an environmentally friendly option

Relevant resources


Images of the menstrual cycle

Fact sheets/booklets/videos

Puberty – things that change for girls, Healthy WA

This Background Note relates to the following Learning Activities: