Editing Endometrium (section)

{{Short description|Inner mucous membrane of the mammalian uterus}}
{{Infobox anatomy
| Name        = Endometrium
| Latin       = tunica mucosa uteri
| Image       = Basic_Female_Reproductive_System_(English).svg
| Caption     = Uterus and [[fallopian tubes]] (uterine tubes). (Endometrium labeled at center right.)
| Width       = 
| Image2      =Proliferative phase endometrium -- high mag.jpg 
| Caption2    =Endometrium in the proliferative phase 
| Precursor   = 
| System      = 
| Part_of     = [[Uterus]]
| Artery      = 
| Vein        = 
| Nerve       = 
| Lymph       = 
}}

The '''endometrium''' is the inner [[epithelium|epithelial]] layer, along with its [[mucous membrane]], of the [[mammal]]ian [[uterus]].  It has a basal layer and a functional layer: the basal layer contains [[stem cell]]s which regenerate the functional layer.<ref name="Gargett">{{cite journal|last1=Gargett|first1=C.E.|last2=Schwab|first2=K.E.|last3=Zillwood|first3=R.M.|last4=Nguyen|first4=H.P.|last5=Wu|first5=D.|title=Isolation and culture of epithelial progenitors and mesenchymal stem cells from human endometrium.|journal=Biology of Reproduction|date=June 2009|volume=80|issue=6|language=en|pages=1136–1145|doi=10.1095/biolreprod.108.075226|pmid=19228591|pmc=2849811}}</ref> The functional layer thickens and then is shed during [[menstruation]] in humans and some other mammals, including other [[ape]]s, [[Old World monkey]]s, some species of [[bat]], the [[elephant shrew]]<ref name="Emera">{{cite journal|last1=Emera|first1=D|last2=Romero|first2=R|last3=Wagner|first3=G|title=The evolution of menstruation: a new model for genetic assimilation: explaining molecular origins of maternal responses to fetal invasiveness.|journal=BioEssays|date=January 2012|volume=34|issue=1|pages=26–35|doi=10.1002/bies.201100099|pmid=22057551|pmc=3528014}}</ref> and the [[Cairo spiny mouse]].<ref>{{Cite journal|last1=Bellofiore|first1=N.|last2=Ellery|first2=S.|last3=Mamrot|first3=J.|last4=Walker|first4=D.|last5=Temple-Smith|first5=P.|last6=Dickinson|first6=H.|date=2016-06-03|title=First evidence of a menstruating rodent: the spiny mouse (Acomys cahirinus)|url=https://www.biorxiv.org/content/10.1101/056895v1|journal=bioRxiv|volume=216|issue=1|language=en|pages=40.e1–40.e11|doi=10.1101/056895|pmid=27503621|s2cid=196624853}}</ref> In most other mammals, the endometrium is reabsorbed in the [[estrous cycle]]. During [[pregnancy]], the glands and [[blood vessel]]s in the endometrium further increase in size and number. Vascular spaces fuse and become interconnected, forming the [[placenta]], which supplies [[oxygen]] and nutrition to the [[embryo]] and [[fetus]].<ref name=histology>[http://www.lab.anhb.uwa.edu.au/mb140/CorePages/FemaleRepro/FemaleRepro.htm Blue Histology - Female Reproductive System] {{Webarchive|url=https://web.archive.org/web/20070221174122/http://www.lab.anhb.uwa.edu.au/mb140/CorePages/FemaleRepro/FemaleRepro.htm |date=2007-02-21 }}. School of Anatomy and Human Biology&nbsp;— The University of Western Australia Accessed 20061228 20:35</ref><ref name=Guyton2006>{{cite book | title =Textbook of Medical Physiology | chapter = Chapter 81 Female Physiology Before Pregnancy and Female Hormones |pages =  1018ff  | edition = 11th |veditors= Guyton AC, Hall JE|publisher = Elsevier Saunders | year = 2006 | isbn = 9780721602400}}</ref> The speculated presence of an endometrial microbiota<ref name="FranasiakScott2015">{{cite journal|last1=Franasiak|first1=Jason M.|last2=Scott|first2=Richard T.|title=Reproductive tract microbiome in assisted reproductive technologies|journal=Fertility and Sterility|volume=104|issue=6|year=2015|pages=1364–1371|issn=0015-0282|doi=10.1016/j.fertnstert.2015.10.012|pmid=26597628 |doi-access=free}}</ref>
has been argued against.<ref name="Baker">{{cite journal|last1=Baker|first1=JM|last2=Chase|first2=DM|last3=Herbst-Kralovetz|first3=MM|title=Uterine Microbiota: Residents, Tourists, or Invaders?|journal=Frontiers in Immunology|date=2018|volume=9|pages=208|doi=10.3389/fimmu.2018.00208|pmid=29552006|pmc=5840171|doi-access=free}}</ref><ref name="Microbiome">{{cite journal|last1=Perez-Muñoz|first1=ME|last2=Arrieta|first2=MC|last3=Ramer-Tait|first3=AE|last4=Walter|first4=J|title=A critical assessment of the "sterile womb" and "in utero colonization" hypotheses: implications for research on the pioneer infant microbiome.|journal=Microbiome|date=28 April 2017|volume=5|issue=1|pages=48|doi=10.1186/s40168-017-0268-4|pmid=28454555|pmc=5410102 |doi-access=free }}</ref>