Does Seminal Fluid Increase Risk of Endometriosis Interview with:
Dr Jonathan McGuane PhD.
Robinson Research Institute and Discipline of Obstetrics and Gynaecology
School of Paediatrics and Reproductive Health
University of Adelaide, Adelaide, South Australia, Australia

Medical Research: What is the background for this study?

Dr. McGuane: Epidemiological studies suggest that endometriosis is present more often in women who report having intercourse during menstruation compared to those who don’t (Filer and Wu, J Reprod Med 1989:887-890). The idea for this study came from our research showing that seminal plasma induces marked changes in the immunology of the female reproductive tract, which are essential for optimal implantation of an embryo and subsequent fetal development. However, some of these immunological changes could increase the likelihood of endometrial tissue developing into an endometriotic lesion if it subsequently ends up in the peritoneum via retrograde menstruation (a la Sampson’s hypothesis). This could help to explain the epidemiological findings cited above. Our study was designed to explore “proof-of-principle” of this concept by exposing human endometrial tissue directly to seminal plasma or control medium in vitro, and transplanting it under the skin of receptive mice.

Medical Research: What are the main findings?

Dr. McGuane: After two weeks, endometrial tissue exposed to seminal plasma was significantly larger than control tissue. This appeared to be the result of increased cell proliferation and tissue survival. Although we hypothesised that an immune-mediated mechanism would underlie the changes induced by seminal plasma, we did not find much evidence to support this idea; however, more work needs to be done on this aspect of the research.

Medical Research: What should clinicians and patients take away from your report?

Dr. McGuane: This paper is the first report on this phenomenon, and was conducted in an animal model. As such, we are not at the stage of being able to make recommendations for patients. We need to translate these findings to women to determine whether the seminal fluid exposure that occurs naturally during intercourse puts women at increased risk of developing endometriosis. If we find that it does, there may be an indication to restrict exposure to seminal plasma around the time of menstruation (e.g. by using barrier methods of contraception) in women with or at risk of the disease. We think that exposure to seminal plasma around the time of menstruation may be a risk factor for the development of endometriosis, but is not the sole underlying cause.

Medical Research: What recommendations do you have for future research as a result of this study?

Dr. McGuane: At this stage, we can only hypothesise as to how seminal plasma could promote this effect in women, although direct contact with lesions is unlikely. Thus, we need to gain a better understanding of how exposure to seminal plasma during normal intercourse could affect the endometrium. It may also be beneficial to pinpoint the precise factor(s) in seminal plasma responsible for this effect, as this could provide clues as to the mechanism(s) underpinning lesion development more broadly and identify potential drug targets.

Finally, it would also be very interesting to explore the potential link between seminal plasma exposure and endometriosis-related pain in women with pre-existing disease.


Am J Pathol. 2015 Apr 8. pii: S0002-9440(15)00079-6. doi: 10.1016/j.ajpath.2015.01.010. [Epub ahead of print]

Seminal Plasma Promotes Lesion Development in a Xenograft Model of Endometriosis.

McGuane JT1, Watson KM2, Zhang J2, Johan MZ2, Wang Z2, Kuo G2, Sharkey DJ2, Robertson SA2, Hull ML3.

[wysija_form id=”1″] Interview with:, & Dr Jonathan McGuane PhD. (2015). Does Seminal Fluid Increase Risk of Endometriosis