Vaginal bleeding between your periods is not unusual, but should be checked by your doctor if it happens more than once or twice.
There are several things that could cause bleeding between periods, such as changes to your hormonal levels, use of hormonal contraception or contraceptive devices, an infection, or an injury, for example.
Changes to your hormonal levels
Some women may experience bleeding about 10-14 days after their period. This is usually caused by a temporary drop in levels of the hormone oestrogen at the time of ovulation (when an egg is released by an ovary). This is quite normal.
Use of hormonal contraception
If you have recently started taking hormonal contraceptives it is not uncommon to experience bleeding between periods due to the drop in hormone levels. This will usually happen around two weeks after your last period, and is often referred to as breakthrough bleeding. Your periods will usually become more regular within six months, and the bleeding between your periods should stop after a month or two. Bleeding between periods can also occur if you forget to take one of your oral contraceptives.
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 to seek help
If you are bleeding very heavily or you feel faint or as if you might pass out, make sure you see your doctor.