Cause of endometriosis symptoms

If you have been diagnosed with endometriosis, there could be a number of different causes.

Retrograde menstruation occurs when menstrual fluid enters back into the pelvic area through the fallopian tubes. Because the fallopian tubes are open-ended and not joined to the ovaries, the menstrual tissue is able to escape and attach to structures outside the uterus, such as the bladder, ovaries and bowel, where the tissue can grow.

While most women will experience some degree of retrograde menstruation, only 6-10% develop endometriosis. This could be due to a variety of causes:


  • Genetics suggests the risk for first degree relatives of women with severe endometriosis is six times higher than for relatives of unaffected women [i]


  • Immune system of women with endometriosis may fail to control or stop the growth of endometrial tissue outside the uterus


  • Oestrogen dominance may occur in women with higher levels compared to progresterone


  • Environmental exposure to certain chemicals or toxins [ii]


[i] Vigano, P. et al. ‘Endometriosis: epidemiology and aetiological factors’ Best Practice & Research Clinical Obstetrics and Gynaecology 2004; 18 (2);177-200

[ii] Bulun, S. E. ‘Endometriosis’ The New England Journal of Medicine 2009; 360:268-79