Survey study, 2019
Does the menstrual cycle affect gut bacteria and immune response related to PMS?
Yes. Antibody levels to gut bacteria change throughout the cycle, peaking at day 28, and these changes are linked to physical symptoms like bloating, anxiety, and breast swelling but not depression. Progesterone appears to drive these changes.
What they did
Cross-sectional study of 40 women aged 18-45 (some with and some without premenstrual symptoms). Women tracked symptoms daily for 28 consecutive days using a standardized scale. Researchers measured blood antibodies to six gram-negative bacteria, plus progesterone and estradiol, at days 7, 14, 21, and 28.
What they found
Antibody levels to gut bacteria peaked at day 28 and were lowest at days 7-14. Changes in antibody levels were significantly associated with physical symptoms (breast swelling, bloating, food cravings) and anxiety. Changes were NOT associated with depressive symptoms. Progesterone levels predicted antibody changes.
What it means for you
Menstrual cycle hormones, especially progesterone, may affect how the gut barrier works, allowing bacterial products to trigger immune responses and physical PMS symptoms. This could explain bloating, anxiety, cravings, and breast tenderness before the period. This is early research on a small group with a novel theory.
40
women in study
28
days of cycle tracked
6
bacterial types tested
About the study
- Original title
- The menstrual cycle may not be limited to the endometrium but also may impact gut permeability
- Authors
- Roomruangwong C, Carvalho AF, Geffard M et al.
- Journal
- Acta neuropsychiatrica
- Year
- 2019
- Study design
- Survey study
- What was tested
- None. Observational study tracking cycle and symptoms.
- Open access
- Yes
- Read the paper
- doi.org/10.1017/neu.2019.30
Topics
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