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HealthInfo Waitaha Canterbury

Irregular periods

Irregular periods means that the length of time between your periods keeps changing. A period is counted from the first day of your last period to the start of your next one.

Irregular bleeding includes:

A normal menstrual cycle may be bleeding for three to eight days, that happens every 25 to 35 days. Most of the blood loss happens in the first three days.

Your monthly cycle is affected by the levels of the hormones estrogen and progesterone in your body. That is why it's common to have irregular periods during puberty, and just before your menopause.

Causes of irregular periods

Changes in your cycle are usually caused by a hormone imbalance that causes your periods to stop or become irregular. These include:

Getting help with irregular periods

Bleeding that occurs between periods, after sex, or after menopause can be abnormal. Often there may not be a cause for this bleeding, but sometimes it can be caused by infection, or very occasionally, cancer. If you have this type of bleeding, it's important that you see your GP straight away, rather than waiting to see if the bleeding happens again.

Make an appointment with your GP if you're worried about any aspect of your periods, including irregular periods. Even if you're not worried, it's worth seeing them if:

Diagnosing irregular periods

It can be helpful to complete a menstrual diary, which is a record of your periods. You can also download a period tracker app, called Clue, for iPhones and Android phones, or Period Tracker for Android phones.

Bring your diary along to your appointment to discuss with your doctor.

At your doctor's appointment, you can expect them to ask you about:

Your doctor may check your height and weight and give you a pelvic examination.

You may also need to have some blood tests to check your hormone and thyroid levels, and in some cases, an ultrasound. You may have to pay for an ultrasound or use your health insurance, but you should talk to your doctor about this.

Treating irregular periods

You might not need any treatment for irregular periods. You may need treatment if you're trying to get pregnant or have a condition causing your irregular periods such as polycystic ovary syndrome (PCOS). Your doctor may suggest that you see a specialist doctor in hormones (endocrinologist) or in women's health (gynaecologist).

You may also wish to pay to see an endocrinologist or gynaecologist privately. You can find a private gynaecologist on Healthpoint.

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Written by HealthInfo clinical advisers. Last reviewed September 2021.


Page reference: 47309

Review key: HIPER-53354