There are roughly 77 million women around the world who are suffering from endometriosis, a condition in which endometrium cells (uterine cells) are found outside the uterus, particularly in the ovaries, vagina, fallopian tubes, bowel or even the bladder.
In rare cases, endometrium cells also attach themselves to the lungs, eyes and even the brain.
In spite of the large number of women who have this condition the causes of endometriosis remain unclear.
Endometriosis currently has no known cure and brings about pain and discomfort in most sufferers and is a cause of infertility for many women.
Individuals suffering from endometriosis can also find they have strained relationships due to dyspareunia, a medical term that means painful intercourse.
Having an understanding partner can be just as important as finding the right doctor.
Below are some of the theories that deal with the possible causes behind endometriosis: Retrograde menstruation: Some experts believe that the menstrual fluid, instead of streaming out of the body via the vagina, flows in reverse back up into the fallopian tubes.
Even though the fallopian tube and the ovaries are connected, there is a small opening where the retrograde menstruation could flow out to the pelvic area.
Some of the endometrium cells (cells that line or coat the uterus) from the menstrual flow can then attach themselves to the body tissues found in the pelvic area, including the ovaries, bladder, fallopian tubes, bowel and even the colon.
These misplaced cells, believing that they are still attached to the uterine lining, swell and shed during future menstrual cycles.
Unfortunately, the newly shed cells cannot exit the body and gets stuck in the pelvic or abdominal area leading to the painful symptoms that characterise endometriosis.
The main problem with this theory is that retrograde menstruation occurs in a high percentage of all women, yet not every women goes onto to develop endometriosis.
This leads us to the next possible cause.
Deficiency of the immune system: As less than 10% of women have endometriosis, a number of experts believe that there is some problem in the immune system of those who suffer from endometriosis.
They say that the immune system should be able to stop the growth of misplaced endometrium cells.
The immune system's role is to attack any foreign bodies within our system and misplaced endometrial tissue is just that.
The immune system should make short work of eliminating these rogue tissues.
For women whose immune system doesn't recognize these alien cells could highlight they have an auto-immune disorder or an immune deficiency.
Hormonal imbalance: At present, there are studies looking into the connection between hormones, particularly estrogen, and the development of endometriosis.
Some believe that an endocrine system deficiency or malfunction can also be an underlying cause of the disease.
Role of genetics: Many believe that genes play a vital role on whether a person will develop endometriosis in the future.
In this particular theory, the ailment could possibly be passed on to your offspring.
If your sister, mother or even cousins have endometriosis, there is an increased chance that you too will have endometriosis.
Exposure to pollutants and other environmental factors: Some studies have shown that one of the causes of endometriosis is the exposure to chemicals and pollutants, particularly dioxins.
Proponents of this theory believe that the more you are exposed to dioxins, which are byproducts of bleached pulp products and pesticides, the higher your chance of developing this ailment.
This list is not exhaustive and there are other risk factors involved.
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