Editing Pyometra (section)

===Hormonal influences and mis-mating shots===
Females that have received [[estradiol]] as a [[mismating shot]] in [[diestrus]] are at risk for more severe disease because [[estrogen]] increases the number of progesterone receptors in the endometrium. 25 percent of females receiving estradiol in diestrus develop pyometra.<ref name=Wingfield>{{cite book|author=Wingfield, Wayne E.|title=Veterinary Emergency Medicine Secrets|year=1997|publisher=Hanley & Belfus |editor=Hanley & Belfus, Inc.|isbn=1-56053-215-7}}</ref>  Pyometra is less common in female cats because progesterone is only released by the ovaries after mating.<ref name=Merck>{{cite web | title = Pyometra | work = The Merck Veterinary Manual | year = 2006 | url = http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/112009.htm | access-date = 2006-12-14 }}</ref> Also in cats, the risk of developing the disease differs depending on breed.<ref>{{cite journal|last1=Hagman|first1=R|last2=Ström Holst|first2=B|last3=Möller|first3=L|last4=Egenvall|first4=A|title=Incidence of pyometra in Swedish insured cats.|journal=Theriogenology|date=1 July 2014|volume=82|issue=1|pages=114–20|pmid=24726694|doi=10.1016/j.theriogenology.2014.03.007|doi-access=free}}</ref>