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Here’s what you need to know about irregular periods and perimenopause

Your Health / Conditions / Women's Health / Here’s what you need to know about irregular periods and perimenopause​​​​​​​

Published on Feb 26, 2020
​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​Authored by Charanjeet Singh, MBBS


Ah, periods. Your period has been a regular monthly companion for decades now. It’s annoying and inconvenient, but consistent nonetheless. The start of menopause – perimenopause – means you can say goodbye to this regularity. In the years leading up to menopause, many women experience irregular bleeding, shorter or longer periods or a lighter or heavier flow.

What are irregular periods?

Irregular is the new normal. While some women simply stop menstruating, most face years of menstrual changes before reaching menopause. Unpredictable periods are a normal and common part of perimenopause, the years leading up to your final period.
Everyone is different, but you may experience:

  • periods that become irregular – longer or shorter than the normal 28-day cycle
  • bleeding that lasts for fewer days or more days than you’re used to
  • a menstrual flow that is heavier or lighter than you’re used to.

What’s causing irregular periods?

A normal 28-day menstrual cycle is controlled by the hormones estrogen and progesterone increasing and decreasing in a regular pattern throughout the month. As you approach menopause, the production of these hormones begins to taper off, and so your periods can become irregular.
But you can still get pregnant. Use birth control during this time if you’re not hoping to add a small person to your life.

When do I need to see a doctor?

Irregular periods are a normal part of perimenopause, but some abnormal bleeding can signal underlying health problems. Talk to your doctor if you notice any of the following:

  • very heavy bleeding
  • bleeding that lasts longer than seven days, or two or more days longer than usual
  • bleeding that occurs more often than every three weeks
  • bleeding that occurs after sex
  • spotting between periods.

It can be hard to judge if you have a ‘very heavy’ menstrual flow. A good way to tell is if your bleeding is not contained within a pad or tampon, or you’re changing a pad or tampon every hour.

Heavy bleeding may also lower your iron levels, causing you to feel tired and weak. Speak to your doctor if you’re concerned about this. Your doctor may order a blood test and evaluate your medical history.

When will the irregular periods end?

Irregular and unpredictable periods are inconvenient, and sometimes embarrassing. But they won’t last forever. For most women, perimenopause lasts between four to eight years. Eventually, your periods will stop altogether.

Talk to your doctor if the symptoms of menopause, including irregular periods, are affecting your daily life. Your doctor can consider the different symptoms you are experiencing, your age, and your overall health – and then talk with you about management options that suit you.

If you are worried about heavy menstrual bleeding, you should talk to your GP.  They will ask you questions to better understand your health, do a blood test and may also do a physical exam.


Last reviewed: 13/05/2020

External Resources

Jean Hailes Foundation
Australasian Menopause Society Fact Sheets

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