Little is understood in regards to the causes of endometriosis. Each case has its own unique characteristics and in turn probable causes will vary on a case-by-case basis. Despite this, there are two key risk factors which are more commonly associated with endometriosis. These are family history and retrograde menstruation.
A woman is seven to ten times more likely to get endometriosis if they have a relative who has the condition. The closer the family relationship with an endometriosis sufferer, the greater the chance a female will also get endometriosis.
Retrograde menstruation is also a common risk factor for endometriosis. This involves the flow of menstrual blood heading back into the vagina through the fallopian tubes and into the pelvis area. This blood contains endometrial tissue. For the majority of women, this tissue will break down and be reabsorbed and no symptoms will be experienced. For those with endometriosis, this tissue may start to grow.
There are a range of other symptoms which may be associated with endometrioses. These include: the arrival of a menstrual cycle before the age of 11 years; recurring menstrual cycles of less than 27 days; delay in childbirth; falling pregnant at a young age; the use of alcohol; and low body weight.