The results of a study published in the journal Fertility and Sterility suggest a possible association between endometriosis and periodontal disease.

Endometriosis occurs when the tissue lining the uterus, the endometrium, begins to grow and shed in places outside of the uterus, such as the pelvis and intestines, as well as the fallopian tubes, ovaries and other areas. When this tissue is shed during the menstrual cycle, the condition causes premenstrual pain, painful and heavy periods, and sometimes infertility. Periodontal disease is the infection and inflammation of the gums, tissues and bone around the teeth.

A contributing factor in the development of endometriosis might be "a defect in the immune system's ability to clear retrograde menstrual flow," suggest Dr. Dan I. Lebovic, of the University of Michigan Health System, Ann Arbor, and colleagues. Autoimmunity has also been implicated in the development of periodontal disease, they note.

To further investigate this relationship, the researchers examined the association between endometriosis and periodontal disease using data from 4,136 women who were enrolled in the National Health and Nutrition Examination Survey from 1999 to 2004.

The results of logistic regression analysis revealed that women with endometriosis had a 57 percent increased risk of having gingivitis and periodontitis compared with women without endometriosis, the researchers report.

Although endometriosis may be the result of multiple factors, it may also "be augmented by an immune response to an infectious agent," Lebovic suggests, and the "potential underlying link between the two diseases may be a generalized, global immune dysregulation."