What is bleeding between periods?

After puberty and before menopause, women experience normal vaginal bleeding each month during their menstrual period. Normal vaginal bleeding, or a “period”, varies widely between women and can be different for you at different stages of your life. Generally, all women experience a menstrual period around once a month, approximately every 21 to 35 days, and it can last anywhere between 1 and 7 days.

Bleeding between periods is any vaginal bleeding that occurs outside of a normal period. Bleeding between periods may be similar to a normal period, may be heavier with a larger blood loss, or may be a very light blood loss (also known as “spotting”). Bleeding between periods may be once off or may last for a number of days.

What can cause bleeding between periods?

There are many things that could cause bleeding between periods, such as changes to your hormones levels, use of hormonal contraception or contraceptive devices, an infection, or an injury.

Other causes of bleeding between periods may include:

• endometriosis
• polyps (growths) in your uterus or cervix
• inflammation of your cervix
• abnormalities in the cervix or uterus
• fibroids
• an ectopic pregnancy or the start of a miscarriage
• cancer

Changes to your hormone levels

Young women often spot, or bleed very slightly, when they ovulate (release an egg from the ovary). It happens about 10 to 14 days after their period and is usually caused by a temporary drop in levels of the hormone oestrogen. This is quite normal.

As well as reduced oestrogen levels, you may also experience other hormonal imbalances, which are completely harmless. This could be as a result of stress, or a recent change of diet.

Girls who have just started their periods and women going through menopause are more likely to have irregular periods, which can be confused with bleeding between periods.

Your doctor may organise a blood test to investigate your hormone levels and will advise you on possible treatments.

Use of hormonal contraception

Bleeding between periods often happens when you start to take hormonal contraceptives. This is because your hormone levels drop. It is also called breakthrough bleeding, and usually happens about 2 weeks after your last period.

Breakthrough bleeding should stop after 1 or 2 months. Your periods will usually become more regular within 6 months. Bleeding between periods can also happen if you forget to take one of your oral contraceptive pills.

However, if bleeding occurs at other points during your menstrual cycle, you should consult your doctor in order to rule out the possibility of other conditions.

Hormonal contraceptives such as hormone containing intra-uterine devices (IUDs) contraceptive injections or rods can also cause breakthrough bleeding or irregular periods. Sometimes this may be because the device isn’t inserted properly, especially if it’s also painful. Check with your doctor as they may be able to give you medicine to control the bleeding and rule out other causes, like an infection.

Infections and injury

Vaginal bleeding between periods may be the result of an infection in the vagina, cervix or uterus. Some sexually transmitted infections, like chlamydia or gonorrhoea, can cause bleeding. A yeast infection, or vaginal thrush, can also cause vaginal irritation and bleeding.

An injury to the vulva, vagina or cervix can cause bleeding between periods. Injuries can result from a variety of methods, including from rough sexual activity or incorrectly inserting or removing something into the vagina, like a tampon.

Changes to the cervix

Bleeding between your periods may be caused by changes in the cells of your cervix. This may be due to inflammation, hormonal changes, a human papilloma virus infection or cervical cancer. If you have bleeding between your periods, your doctor will be able to examine your cervix using a speculum and can take a sample of cells for a cervical screening test.

Endometriosis

Sometimes bleeding between periods is caused by endometriosis. Endometriosis is when some of the cells similar to those that line the uterus (womb), called the endometrium, grow in other parts of the body. They usually grow in the pelvis, but can move to almost any part of the body.

Endometriosis can also cause heavy bleeding, irregular bleeding, painful periods and longer periods than normal.

Endometriosis is common and it can make it difficult to get pregnant. If you think you may have endometriosis, talk to your doctor as there are many different treatments available.

Fertility treatments

Vaginal bleeding may occur during certain fertility procedures — for example, during the egg collection stage of IVF treatment. Usually it is mild to moderate bleeding with some cramping. However, if you experience heavy bleeding, you should contact your fertility clinic or doctor for advice

When should I see my doctor?

Bleeding between periods is common — in fact, it happens to most women at some point during their lives. However, it is not considered normal to bleed frequently in one month, or to bleed between your periods for several months. Bleeding after having sex should always be discussed with your doctor. There are many possible causes for bleeding between periods and a lot of them aren’t serious, but you should speak to your doctor if you bleed between periods as it can occasionally signal something serious.

How is the cause of bleeding between periods diagnosed?

Your doctor may ask you about your general health and the nature of your normal periods and about the bleeding between your periods. They may also ask whether you could be pregnant.

Your doctor might feel your tummy, do an internal examination to check your vagina and look at your cervix using a medical device called a speculum. They may also swab your vagina to test for infections and take a cervical screening test to see if there are any changes in your cervix. You doctor may also ask you to do a blood test, a pregnancy test or go for an ultrasound.

Your doctor may also refer you to a gynaecologist, who is a medical doctor who specialises in women’s health.

How is bleeding between periods treated?

If you have not yet discussed your vaginal bleeding with your doctor, its important you make an appointment to do so, as vaginal bleeding cannot be treated without knowing the cause.

If your doctor has diagnosed the cause of your bleeding, you can treat the bleeding by following their advice, such as by taking a course of antibiotics if you have an infection, or by changing to a different form of contraception if the bleeding is caused by the contraception you have been taking. If the bleeding is light and isn’t bothering you, and a serious cause of the bleeding has been ruled out, it may not be necessary to do anything at all.