One fact about menstruation completely changed the way I think about periods: every month, the body sheds an entire organ.
Most of us learn that menstruation is the shedding of the uterine lining. What often goes unmentioned is that the endometrium, which is the tissue lining the inside of the uterus, is considered a temporary organ [1-2]. Throughout the duration of the cycle, the endometrium grows an intricate network of blood vessels, immune cells, glands, and supportive tissue in preparation for a possible pregnancy. If pregnancy does not occur, that organ-like structure is shed during the menstrual phase [1-2].
When I first learned this, I was surprised. We tend to talk about periods as if they are a minor inconvenience, yet the body is carrying out an incredibly complex biological process: building and then shedding a highly specialized structure every single month. That takes energy [3-4].
Understanding menstruation in this way can also help explain why many may feel tired, experience cramping, need more sleep, and/or simply have less capacity during their period [3-4]. While every person experiences menstruation differently, it makes sense that the body may benefit from additional rest while it undergoes this process. Unfortunately, modern life rarely acknowledges this reality. School, work, sports, and social commitments often expect someone to show up the same way every day of the month. There is little room for the natural fluctuations that come with a hormonal cycle and the physical and psychological changes associated with it. As a result, many may feel pressured to ignore what their bodies are telling them [5].
Recognizing menstruation as the shedding of an organ doesn’t mean that we should stop our normal activities and responsibilities. Rather, this understanding invites a different perspective that views rest, flexibility, and self-care during menstruation as ways to welcome and celebrate this remarkable biological event.
The next time someone dismisses a period as “just bleeding,” remember that the body is doing far more than that. Our bodies are building, shedding, and regenerating an organ. This month, consider one small ritual of rest, nourishment, or reflection that you can add to your menstrual phase. It doesn’t have to be dramatic, just a little something to acknowledge the remarkable work your body is doing and to honor this natural, cyclical change.
References
- Critchley, H. O. D., Maybin, J. A., Armstrong, G. M., & Williams, A. R. W. (2020). Physiology of the endometrium and regulation of menstruation. Physiological Reviews, 100(3), 1149–1179. https://doi.org/10.1152/physrev.00031.2019.
- Evans, J., Salamonsen, L. A., Winship, A., Menkhorst, E., Nie, G., Gargett, C. E., & Dimitriadis, E. (2016). Fertile ground: Human endometrial programming and lessons in health and disease. Nature Reviews Endocrinology, 12(11), 654–667. https://doi.org/10.1038/nrendo.2016.116.
- Benton, M. J., Hutchins, A. M., & Dawes, J. J. (2020). Effect of menstrual cycle on resting metabolism: A systematic review and meta-analysis. PLOS ONE, 15(7), e0236025. https://doi.org/10.1371/journal.pone.0236025.
- Hurtová, A., Gimunová, M., & Beníčková, M. (2026). Resting metabolic rate fluctuations across the menstrual cycle: A systematic review. Frontiers in Physiology, 17, 1778735. https://doi.org/10.3389/fphys.2026.1778735.
- Raves, D. M., Herrera, W. D., Darnell, M. E., Rice, T., Friedman, C., Moratti, S. C., Sims, S. T., Sihanath, W. B., Ehrhardt, S. N., & Phillips, A. (2025). A survey assessing the impact of symptoms related to the menstrual cycle and perceptions of workplace productivity: considerations for employer-sponsored menstrual health programs. BMC Women’s Health, 25, Article 418. https://doi.org/10.1186/s12905-025-03833-w.
