If you are bleeding very heavily or you feel faint or that you might pass out, call triple zero (000) immediately and ask for an ambulance. If calling triple zero (000) does not work on your mobile phone, try calling 112.

What can cause bleeding between periods?

There are several 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 take 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.

Other 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.

Endometriosis

Sometimes bleeding between periods is caused by endometriosis, a problem with the lining of the womb. It 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.