Why Do People Have Periods When Most Mammals Don't?

Few mammals actually get periods every month, or even at all, but why? Understanding what menstruation really is and why it happens could help ease symptoms & treat conditions that stem from the reproductive system.

Hosted by: Olivia Gordon

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Sources:

https://onlinelibrary.wiley.com/doi/full/10.1002/bies.201100099
https://academic.oup.com/biolreprod/article-abstract/91/4/98,%201-8/2434351
https://academic.oup.com/humupd/article/21/6/748/628724
https://www.jstor.org/stable/3036558
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4000068/
https://academic.oup.com/biolreprod/article/99/1/196/4898004 https://academic.oup.com/humrep/article/9/7/1202/746307
https://www.journals.uchicago.edu/doi/10.1086/419369
https://academic.oup.com/humrep/article/25/12/2944/552315
https://www.ncbi.nlm.nih.gov/pubmed/8693059
https://www.ncbi.nlm.nih.gov/pubmed/27862405
https://www.jstor.org/stable/2831191
https://www.ncbi.nlm.nih.gov/pubmed/12262232
http://jpet.aspetjournals.org/content/52/2/179
https://vcahospitals.com/know-your-pet/estrus-cycles-in-dogs
https://www.newyorker.com/magazine/2019/01/14/the-history-of-blood
https://psmag.com/news/a-brief-history-of-menstrual-blood-myths
https://helloclue.com/articles/culture/top-euphemisms-for-period-by-language
https://www.healthline.com/health/period-poop
https://ucmp.berkeley.edu/mammal/eutheria/placental.html
http://www.vivo.colostate.edu/hbooks/pathphys/reprod/placenta/structure.html
https://www.nature.com/scitable/topicpage/chromosomal-abnormalities-aneuploidies-290/

Images:

https://en.wikipedia.org/wiki/File:Trajan%27s_market.jpg

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