What causes bleeding between periods?

There are many different causes of bleeding between periods. Some may not be anything to worry about, but seek medical advice if you're concerned.

If you are postmenopausal, or think you could be, find out more about postmenopausal bleeding.

Hormonal contraceptives

Irregular bleeding, such as bleeding between periods, is common during the first few months of starting hormonal contraception, such as the:

• combined pill
• progestogen-only pill
• contraceptive patch
• contraceptive implant or contraceptive injection
• intrauterine system (IUS) or hormonal coil

If you're concerned about bleeding or it lasts longer than a few months, you should seek medical advice.

You may also bleed between periods if you:

• miss any combined pills
• miss any progestogen-only pills
• have a problem with your patch or vaginal ring
• are sick or have diarrhoea when taking the pill

Other causes

Some other causes of bleeding between periods include:

• taking the emergency contraceptive pill
• injury to the vagina – for example, from having penetrative sex
• recently having an abortion – seek medical advice if you're bleeding heavily
• sexually transmitted infections (STIs) such as chlamydia – it's a good idea to get tested if you've recently had unprotected sex with a new partner
• recently having a miscarriage
• changes in hormone levels – this is common in women approaching the menopause
• stress
• vaginal dryness
• harmless changes to the neck of the womb (cervix) – this may be called cervical ectropion or cervical erosion
• cervical cancer – if you're aged 25 to 64, you should be having regular cervical screening to detect any changes to your cervix
• womb (uterus or uterine) cancer – this is more common in post-menopausal women
• vaginal cancer or vulval cancer
• cervical or endometrial polyps – non-cancerous (benign) growths in the womb or the lining of the cervix
• fibroids

When to seek medical advice

If you have any unusual vaginal bleeding between your periods, you should:

• see a GP
• visit a sexual health or genitourinary medicine (GUM) clinic

A healthcare professional will talk to you about your symptoms. Depending on your situation, they may suggest doing some tests, such as:

• tests for STIs, which may include an examination of your genitals
• blood tests
• a pregnancy test
• cervical screening, if you're aged 25 to 64 and not up-to-date with these
• a pelvic ultrasound scan

To diagnose some conditions, you may need an examination, such as:

• a speculum examination – a smooth, tube-shaped tool (a speculum) is inserted into your vagina to examine your vagina and cervix
• an internal examination of your vagina with gloved fingers (bimanual examination)