I was searching for the recent studies and information related to seasonal changes and menstrual cycles and found an interesting story about famous American explorer and physician, Frederick Cook.
It is claimed that the earliest documented link between sunlight and the menstrual cycle dates back to Frederick Cook's observations during his Arctic expedition in 1897.
Before going into detail, a disclaimer, ha-ha once tried to work with a legal team, never stop this habit of adding disclaimers: there is no claimed data to support these statements.
So, let's proceed, he noted that Inuit women did not menstruate during the 4 months of darkness in the northwest coast of Greenland. As sunlight returned in spring, Inuit women resumed menstruation, and births occurred approximately 9 months later.
Cook also noticed similar effects among his team, with decreased sexual desire and menstruation in the winter months when sunlight was scarce.
Of course I found studies that state that during summer time cycles become shorter (not clinically relevant, around 1 day shift). So, what are your thoughts? Has time changed physiology? More than 100 years have passed, so??? Or there are confounding factors that remain undisclosed...
#menstrualcycle #seasonal_changes #research
References:
1. Vidafar, P., & Spitschan, M. (2023). Light on Shedding: A Review of Sex and Menstrual Cycle Differences in the Physiological Effects of Light in Humans. Journal of biological rhythms, 38(1), 15–33.
2. Li, H., Curry, C. L., Fischer-Colbrie, T., Onnela, J. P., Williams, M. A., Hauser, R., Coull, B. A., Jukic, A. M. Z., & Mahalingaiah, S. (2024). Seasonal variations of menstrual cycle length in a large, US-based, digital cohort. International journal of hygiene and environmental health, 256, 114308.
