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What is a period?

If you’re not pregnant, your hormones send a signal to your uterus to shed its lining.

This is your period

Once your period starts, the cycle begins again. A menstrual cycle is measured from the first day of your period (day one of your cycle) to the day before your next period. The average length of a menstrual cycle is 28 days, but every woman’s cycle is different.

The average length of a menstrual cycle is 28 days. Is it normal to miss one or more periods? It’s normal to miss periods at different times in your life.

For example: (your final menstrual period).

When you don’t get your period at all it’s called ‘amenorrhoea’

This can be short-term or long-term.

If your period is late or stops, it’s important to check if you’re pregnant

What causes absent periods? Hormonal imbalance is the most common cause of absent periods.

This can be caused by: low body weight and poor nutrition (i.e. Asherman’s syndrome (a rare genetic condition where scar tissue forms inside the uterus).

Treating absent periods depends on the cause

If another condition is causing amenorrhoea, your doctor will usually treat that first.

Treatments include: specialist care (in the case of an eating disorder)

See your doctor if: you have noticed changes in the pattern of your periods.

It’s a good idea to record information about your periods to discuss with your doctor.

For example, when you get your period, the length and heaviness of your period and how your periods impact your life. A period is when you bleed from your vagina every month.

Periods are part of your body’s menstrual cycle The menstrual cycle The menstrual cycle prepares your body for pregnancy Menstrual cycles can change over time.

For example, when you first start getting your periods while pregnant while breastfeeding in the lead-up to menopause Absent periods (amenorrhoea) Primary amenorrhoea is Secondary amenorrhoea polycystic ovarian syndrome (PCOS) pituitary or thyroid disease excessive exercise eating disorders such as anorexia nervosa ) weight gain severe anxiety and stress travel menopause Treatment options hormone therapy medication lifestyle changes surgery nutritional advice When to see your doctor your periods have not started by the age of 16 to 17 you have missed 3 or more periods in a row you have had fewer than 9 periods in a year More information For more detailed information, related resources, articles and podcasts, visit Jean Hailes for Women’s Health Where to get help GP (doctor) Gynaecologist Sexual Health Michigan Butterfly Foundation Jean Hailes for Women’s Health .

Key Points

  • If your period is late or stops, it’s important to check if you’re pregnant
  • What causes absent periods? Hormonal imbalance is the most common cause of absent periods
  • This can be caused by: low body weight and poor nutrition (i.e
  • Treating absent periods depends on the cause
  • Treatments include: specialist care (in the case of an eating disorder)