Two periods in one month

An adult woman’s menstrual cycle can range in length from 24 to 38 days and in teenage girls it can last even longer. Based on how long your cycle normally lasts, if you think you’re having a second period in that stretch of time, it is important to determine if it is just spotting or menstrual bleeding.

In most cases, having two periods in a month occasionally is not serious. However, if you’re frequently having two periods in one month, you may have an underlying health condition.

What causes menstruation twice a month?

Two periods in one month can be caused by having a shorter menstrual cycle or by an underlying health condition that causes vaginal bleeding.

Reasons your menstrual cycle may suddenly become shorter include stress, illness, extreme weight loss or gain, reacting to hormonal birth control and a failure in the egg releasing from your ovary (anovulation).

In young girls, puberty can cause shorter menstrual cycles, while in older women, this can occur due to menopause.

Health conditions that cause more frequent periods

Health conditions that can cause sudden, shorter menstrual cycles include:

  • Fibroids
  • Hyperthyroidism or hypothyroidism
  • Miscarriage — if you are pregnant, a miscarriage can cause heavy bleeding; contact your doctor or midwife urgently if this occurs
  • Pregnancy — early pregnancy can cause spotting, however, you should still tell your doctor or midwife
  • Sexually transmitted infections (STIs) — STIs can cause vaginal bleeding and discharge
  • Uterine cysts

Risk factors for frequent menstruation

You are more at risk of having two periods in one month, if you have a family history of uterine cysts, fibroids or early onset menopause.

When to see a doctor for frequent menstruation

You should see your GP if you are menstruating more often and have: 

  • Dark clots in your menstrual blood
  • Heavy periods
  • Lower abdominal pain that doesn’t get better after a few days
  • More menstrual cramps than usual
  • Pain during sex
  • Spotting or bleeding in between your periods — you may mistake this for two periods in one month

Treatment for frequent menstruation

The treatment for frequent menstruation depends on the underlying cause. If you have just started having periods or you normally have shorter menstrual cycles, you won’t need any treatment. However, if your doctor is concerned that the frequency of blood loss due to your periods is causing anaemia, they may suggest taking iron supplements.

In some cases, hormonal birth control may be recommended to treat frequent menstruation. 

Frequent menstruation FAQs

Can two periods in a month mean pregnancy?

If you are having periods, then you are not pregnant. However, vaginal spotting, which can occur during early pregnancy, can sometimes be mistaken for a period. If you are pregnant and having any vaginal bleeding, you should tell your doctor or midwife. 

Is it normal to get your period again after a week?

Hormonal changes can cause you to stop and then restart your period occasionally. However, if this frequently occurs, you should see your GP as you may have an underlying health condition. 

Is it normal to have a period every two weeks during perimenopause?

You can develop shorter periods, where you may have two periods in one month, when menopause starts. However, if you aren’t sure if you are menopausal and are frequently experiencing bleeding in between your periods, which may be mistaken for two periods in one month, you should see your GP. 

When do you ovulate if you have two periods a month?

If your cycle is 28 days, you will ovulate around day 14. If your cycle is shorter, then the ovulation is brought forward accordingly eg if you have a 20-day menstrual cycle, you will ovulate around day six. 

We hope you've found this article useful, however, it cannot be a substitute for a consultation with a specialist

If you're concerned about symptoms you're experiencing or require further information on the subject, talk to a GP or see an expert consultant at your local Spire hospital.

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Author Information

Cahoot Care Marketing

Niched in the care sector, Cahoot Care Marketing offers a full range of marketing services for care businesses including: SEO, social media, websites and video marketing, specialising in copywriting and content marketing.

Over the last five years Cahoot Care Marketing has built an experienced team of writers and editors, with broad and deep expertise on a range of care topics. They provide a responsive, efficient and comprehensive service, ensuring content is on brand and in line with relevant medical guidelines.

Their writers and editors include care sector workers, healthcare copywriting specialists and NHS trainers, who thoroughly research all topics using reputable sources including the NHS, NICE, relevant Royal Colleges and medical associations.


The Spire Content Hub project was managed by:

Lux Fatimathas, Editor and Project Manager

Lux has a BSc(Hons) in Neuroscience from UCL, a PhD in Cellular and Molecular Biology from the UCL Institute of Ophthalmology and experience as a postdoctoral researcher in developmental biology. She has a clear and extensive understanding of the biological and medical sciences. Having worked in scientific publishing for BioMed Central and as a writer for the UK’s Medical Research Council and the National University of Singapore, she is able to clearly communicate complex concepts.

Catriona Shaw, Lead Editor

Catriona has an English degree from the University of Southampton and more than 12 years’ experience copy editing across a range of complex topics. She works with a diverse team of writers to create clear and compelling copy to educate and inform.

Alfie Jones, Director — Cahoot Care Marketing

Alfie has a creative writing degree from UCF and initially worked as a carer before supporting his family’s care training business with copywriting and general marketing. He has worked in content marketing and the care sector for over 10 years and overseen a diverse range of care content projects, building a strong team of specialist writers and marketing creatives after founding Cahoot in 2016.