Marriage

===Temporary marriages===
Several cultures have practised temporary and conditional marriages. Examples include the [[Celts|Celtic]] practice of [[handfasting]] and fixed-term marriages in the Muslim community. Pre-Islamic Arabs practiced a form of temporary marriage that carries on today in the practice of [[Nikah mut'ah]], a fixed-term marriage contract. The Islamic prophet [[Muhammad]] sanctioned a temporary marriage – [[Nikah mut'ah|sigheh]] in [[Iran]] and muta'a in [[Iraq]] – which can provide a legitimizing cover for sex workers.<ref>{{Cite book
  | last = İlkkaracan
  | first = Pınar
  | title = Deconstructing sexuality in the Middle East: challenges and discourses
  | url = https://books.google.com/books?id=pnGwP9-FhxYC&pg=PA36
  | publisher =Ashgate Publishing, Ltd.
  | year = 2008
  | page = 36
  | isbn = 978-0-7546-7235-7}}
</ref> The same forms of temporary marriage have been used in Egypt, Lebanon and Iran to make the donation of a human ova legal for [[in vitro fertilisation]]; a woman cannot, however, use this kind of marriage to obtain a sperm donation.<ref>{{cite journal|last=Inhorn|first=Marcia|title=Making Muslim Babies: IVF and Gamete Donation in Sunni versus Shi'a Islam|journal=Culture, Medicine and Psychiatry|year=2006|volume=30|issue=4|pages=427–50|doi=10.1007/s11013-006-9027-x|pmid=17051430|pmc=1705533}}</ref> [[Nikah mut'ah#Western views|Muslim controversies related to Nikah Mut'ah]] have resulted in the practice being confined mostly to [[Shia Islam|Shi'ite]] communities. The matrilineal [[Mosuo]] of China practice what they call "walking marriage".