Editing Meconium aspiration syndrome (section)

== Prevalence ==

1 in every 7 pregnancies have MSAF and, of these cases, approximately 5% of these infants develop MAS.<ref name=":0" /> MSAF is observed 23-52% in pregnancies at 42 weeks. Therefore, the frequency of MAS increases as the length of [[gestation]] increases, such that the prevalence is greatest in post-term pregnancies. Conversely, [[preterm birth]]s are not frequently associated with MSAF (only approximately 5% in total contain MSAF). The rate of MAS declines in populations where labour is induced in women that have pregnancies exceeding 41 weeks.<ref name=":3" /> There are many suspected pre-disposing factors that are thought to increase the risk of MAS. For example, the risk of MSAF is higher in African American, African and Pacific Islander mothers, compared to mothers from other ethnic groups.<ref>{{Cite journal|last1=Sehaghatian|first1=MR|last2=Othman|first2=I|last3=Hossain|first3=MM|last4=Vidyasagar|first4=D|date=2000|title=Risk of Meconium-Stained Amniotic Fluid in Different Ethnic Groups|journal=J Perinatol|volume=20|issue=4 |pages=257–261|doi=10.1038/sj.jp.7200367|pmid=10879341 |doi-access=free}}</ref><ref name=":5">{{Cite journal|last1=Swarnam|first1=K|last2=Soraisham|first2=AS|last3=Sivanandan|first3=S|date=2012|title=Advances in the Management of Meconium Aspiration Syndrome|journal=International Journal of Pediatrics|volume=2012|page=359571|doi=10.1155/2012/359571|pmc=3228378|pmid=22164183|doi-access=free}}</ref>