Non-randomised trial, 2020
Does inflammation increase in the uterus and blood during menstruation?
Yes. A specific inflammation trigger called the NLRP3 inflammasome activates in uterine cells just before menstruation and releases inflammatory chemicals into the bloodstream.
What they did
A study examining inflammasome activation in uterine tissue, blood, and menstrual fluid across the menstrual cycle. Tissue samples were from at least 8 women per cycle phase and blood from at least 9 per phase. Menstrual fluid was from 18 women on day 2 of their period. Cells from 10 women were grown in a lab and exposed to hormone withdrawal to simulate menstruation.
What they found
Components of the NLRP3 inflammasome appeared in uterine cells immediately before menstruation. In the lab model, when hormones were withdrawn from uterine cells, inflammasome components activated and released inflammatory chemicals (IL-1beta and IL-18). These same inflammatory chemicals were detected in women's blood during menstruation and in menstrual fluid.
What it means for you
Menstruation is a naturally inflammatory process involving specific molecular pathways. This might help explain why some women have systemic symptoms during their period. However, this was a lab-based study with small tissue samples, so we don't know how these inflammation patterns relate to PMS or PMDD symptoms.
18
Women providing menstrual fluid
≥8
Tissue samples per cycle phase
10
Women providing cells for lab model
About the study
- Original title
- Endometrial inflammasome activation accompanies menstruation and may have implications for systemic inflammatory events of the menstrual cycle
- Authors
- Azlan A, Salamonsen LA, Hutchison J et al.
- Journal
- Human reproduction (Oxford, England)
- Year
- 2020
- Study design
- Non-randomised trial
- Participants
- 18
- Read the paper
- doi.org/10.1093/humrep/deaa065
Topics
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