Your periods

A period, or ‘menstruation’, is a flow of blood from your vagina that is caused by a build of blood on the lining of the uterus in response to your normal monthly hormone cycle. It usually lasts between three to seven days (with the blood flow usually starting heavy and getting lighter over this time). Most females get their period once a month, but anywhere between every three and six weeks is normal.

Your first period

Girls often get their first period (menstruation) at around 12 or 13 years old, but it can happen at earlier or later ages for some girls. When a girl begins her periods, they may not be very regular at first. This means you might not know when to expect your next period. If you haven’t started having periods by the age of 16 years, see a health professional.

What causes periods?

Monthly periods are triggered by hormones that send a message to the uterus to prepare for a possible pregnancy. These hormones make the lining of the uterus thick so that if an egg is fertilised by male sperm, it can implant safely in the uterus wall. If the egg isn’t fertilised and no pregnancy occurs, the uterus sheds the thick lining. The blood that leaves the vagina during the period is due to the uterus lining coming away. This process continues to happen monthly until a woman reaches her late 40s to early 50s when her hormones decrease and her periods stop (this is called menopause).

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How should I manage my periods?

You will need to use tampons and/or pads during periods to soak up blood. Change these regularly (every couple of hours at the start of the period, and then every 4 to 8 hours). Tampons and pads with blood on them will have an unpleasant smell and can cause infections if left unchanged for too long.

What if my period isn’t on time?

Sometimes, your period may not come when it’s due or you may miss one month altogether. Late or missed periods can be due to:

• pregnancy
• varying length of menstrual cycle
• stress, emotional upset and/or fatigue (tiredness)
• a major change in your normal routine (eg. going to boarding school, backpacking overseas)
• excessive weight loss (losing a lot of weight in a short period of time)
• excessive exercise
• hormone disturbance (due to medication for example)
• coming off the combined oral contraceptive pill, or
• following depo-provera (an injectable contraceptive).

More info

• Find out more about pregnancy
• Find out more about periods from Family Planning Queensland website