Normally endometrial tissue grows only in the uterus and is shed each month during menstruation. Women with endometriosis have endometrial tissue growing in the Fallopian tubes, ovaries, and other sites within the pelvis, or in rare cases, outside of the pelvic area. It is found in women who are childless or who have children late in life. Women with shorter menstrual cycles and longer periods are also believed to be at higher risk of endometriosis.
"Our study has an important public health message for women, especially at a time when many women seeking infertility care have endometriosis as their primary diagnosis," said Harvey Kliman, M.D., lead author of the study and a research scientist in the Department of Obstetrics and Gynecology at Yale School of Medicine. "Our study suggests that tampon use could be one of the strongest protectors against endometriosis."
The study, published in the June issue of the journal Gynecologic and Obstetrical Investigation, looked at whether sexual behaviors, orgasm, tampon use and douching during menstruation modifies the risk of endometriosis. Some 2,012 members of the Endometriosis Association, as well as their friends who are not affiliated with the organization, completed mailed surveys.
Although douching during menstruation did not appear to lessen a woman’s risk of developing endometriosis, Kliman said sexual activity, orgasm and tampon use seemed to play a role in lessening the risk of developing the condition.
Among the women with endometriosis, 26.5 percent said they sometimes or often engaged in sexual activity during menstruation. Among women who are free of the disease, 34.6 percent said they sometimes or often engaged in sexual activity during menstruation. Statistical analysis revealed that women who sometimes or often engaged in sexual activity during menstruation are 1.5 times less likely to have endometriosis than women who do not engage in sexual activities during menstruation. The statistics were roughly the same for women who experienced orgasm during menstruation.
Tampon use appeared to have an even more significant protective effect. Women with endometriosis were less likely to use only tampons during menstruation (11.6 percent) as compared to women without the disease (20.9 percent). About the same number of women in each group reported using both pads and tampons. The number of women with endometriosis who used only pads was 31.3 percent, compared with 22.1 percent for women who do not have the condition. Statistical analysis of these data revealed that women who only used tampons were 2.6 times less likely to have endometriosis compared to women who used pads or pads and tampons.
Kliman said a back up of menstrual fluid in the pelvic cavity is currently believed to play a prominent role in the pathogenesis of endometriosis. As a result, it was hypothesized that tampon use, douching and sexual activity, especially with orgasm, at the time of menstruation would serve to enhance retrograde flow and heighten the chances of developing endometriosis.
"To our surprise, sexual behavior, orgasm and tampon use during menstruation were found to be less frequent among women with endometriosis compared to controls," Kliman said. "It may be that uterine contractions that are part of the female orgasm induces more effective menstrual fluid clearance of the uterine cavity, which in turn may facilitate cervical outflow. Further, the use of tampons may be more efficient at the removal of menstrual fluid compared to the use of pads."
The study was supported by the National Institute of Child Health and Human Development of the National Institutes of Health, as well as by the Southern Connecticut State University Graduate Student Affairs Committee Research Award.