Irregular Menstrual Bleeding

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• Irregular Menstrual Bleeding

Medically Reviewed November 2023, by Dr. Susan Mayou (GMC: 2405092) - founder of the Cadogan Clinic and one of the world's leading dermatologists

What are the causes of bleeding between periods?

There are a number of different things that can cause bleeding between periods:

• Hormonal contraceptives: Irregular bleeding and bleeding between periods are common during the first few months of commencing hormonal contraceptives, including the combined oral contraceptive pill, progestogen-only pill, an intrauterine system (IUS) such as the mirena, implant, injection or contraceptive patch. You may experience bleeding between periods if you miss a dose of the pill, are experiencing vomiting and/or diarrhoea or if your IUS has moved or come out. If the bleeding lasts for more than a few months, if you are experiencing any other symptoms or if you have any other concerns, you should seek medical advice.
• Emergency contraception: Taking emergency contraception, also known as the morning after pill, can cause changes in your next period, such as making it come on earlier or later than usual.
• Perimenopause: Perimenopause is the first stage of menopause, when a woman starts to see the first symptoms of menopause, such as experiencing hot flushes. At this stage, you are still having menstrual periods, although these may be becoming more irregular.
• Polycystic Ovary Syndrome (PCOS): Polycystic Ovary Syndrome (PCOS) is a condition that affects the function of a woman’s ovaries.  Irregular or absent periods are a common symptom of PCOS. This is caused by irregular ovulation or a failure to ovulate.
• Fibroids: Fibroids are benign (noncancerous) growths made up of muscle and fibrous tissue that develop in or around the uterus and can range anywhere from the size of a pea to the size of a melon. Fibroids can cause heavy, painful and irregular bleeding. In rare cases, fibroids may cause infertility and problems in pregnancy.
• Polyps: Cervical polyps are overgrown pieces of tissue protruding from the delicate skin of the cervix or the surface of the cervical canal. Most cervical polyps are benign, however a small percentage of polyps are abnormal and may develop into cancer if left untreated. Polyps can cause bleeding between periods, heavy periods and bleeding after sex.
• Sexually Transmitted Infection (STI): STIs, including chlamydia and gonorrhoea, can cause bleeding in between periods. These both require treatment with antibiotics.
• Vaginal injury: Tears or injury to the vagina can cause bleeding in between periods. Injury may be caused by vigorous sexual intercourse or putting a foreign object into the vagina.
• Miscarriage: Bleeding in between periods can be a sign of an early miscarriage.
• Vaginal dryness: Women suffering from vaginal dryness may experience bleeding in between periods. Vaginal dryness can be caused by a number of things, including menopause, certian medications, using perfumed soaps, cancer treatment or an underlying medical condition.
• Cervical ectropion: Sometimes referred to as cervical erosion, cervical ectropion is when the delicate cells that line the cervical canal spread onto the surface of the cervix. Bleeding between periods and bleeding after sex are common symptoms of cervical ectropion.
• Cervical cancer: Bleeding between periods and bleeding after sex are common symptoms of cervical cancer. Women and anyone with a cervix who are aged 25 to 64 should have regular cervical screening tests to detect any abnormal cells which may develop into cancer.
• Uterine cancer: Although this particular type of cancer is most common in post-menopausal women, women over 40 who are experiencing bleeding between periods should see a doctor to rule out the possibility of uterine cancer.
• Vaginal or vulval cancer: Vaginal cancer is very rare and vulval cancer is rare in women aged under 50 who have not yet been through the menopause. However, bleeding or blood-stained discharge in between periods can be symptoms of vaginal and vulval cancers and you should seek prompt medical advice.

When should I be concerned about bleeding between periods?

It is important to know what is normal for you. If you notice any changes during your periods, then you should start by tracking these on the calendar. If you are experiencing irregular bleeding that persists, comes back, or gets worse, then you should see a doctor. Bleeding after sex and bleeding after menopause are also issues that really need to be explored further.

It is particularly important to see a doctor if the bleeding between periods or irregular bleeding is also accompanied by other symptoms, such as abnormal vaginal discharge, pelvic or abdominal pain, fever and dizziness. It is important to tell the doctor if you are experiencing any other symptoms in order to help them make a diagnosis and treat any health problem promptly.

You should also seek medical advice if you have periods more often than every 21 days or less often than every 35 days, if your period lasts for longer than seven days, if there is a major difference between you longest and shortest menstrual cycle (at least 20 days difference) or you are having irregular periods and are struggling to conceive.

What treatment options are available for Irregular Menstrual Bleeding?

The treatment depends on the root cause of the irregular menstrual bleeding. Depending on the diagnosis, the doctor may decide on one of the following treatments:

• Hormonal contraceptives: Hormonal contraceptives, such as pills or an IUD, will help to regulate periods. These are often prescribed to help with conditions such as Polycystic Ovary Syndrome (PCOS).
• Vaginal oestrogen therapy: This vaginal atrophy treatment involves delivering oestrogen directly into the vagina, via a cream, suppository or oestrogen ring. This is used to help women suffering from vaginal atrophy, which causes vaginal dryness.
• Systemic hormone therapy: More commonly known as hormone replacement therapy (HRT), this is given in pill form and taken orally. It is used to treat common menopause symptoms.
• Polyp removal: A special instrument is used to twist cervical polyps and pull them off, before removing them via the vagina. Anaesthetic is not usually needed, although sometimes a local anaesthetic may be used to numb the cervix if the polyp being removed is particularly large.
• Myomectomy: Sometimes referred to as fibroidectomy, myomectomy is a surgery to remove fibroids from the uterus. Unlike a hysterectomy, a myomectomy just removes the fibroids but leaves the uterus intact, meaning you can still get pregnant.
• Laparoscopy: This minimally-invasive procedure requires a small incision to allow a small tube with a light and camera into the body. A laparoscopy can be used to treat fibroids.
• Hysterectomy: A surgical procedure to remove the uterus is carried out to treat a range of health conditions that affect the female reproductive system, such as fibroids and gynaecological cancers. This is a major operation and a hysterectomy is usually only considered if all other treatments have not worked.
• Antibiotics: If chlamydia or gonorrhoea are the cause of your bleeding between periods, you will be prescribed antibiotics to treat the infection.