title: Is there a seasonal variation in the diagnosis of oligohydramnios?
abstract: OBJECTIVE
  We hypothesized that oligohydramnios would be diagnosed more frequently in the warm summer months when dehydration might be more common.
  
  
  METHODS
  The clinical diagnosis of oligohydramnios was extracted from the databases of four completed National Institute of Child Health and Human Development Maternal Fetal Medicine Units Network protocols. These data were stratified by quarter of delivery and compared using Fisher's Exact Test.
  
  
  RESULTS
  The clinical diagnosis of oligohydramnios was made more frequently in deliveries occurring in the summer months of June, July and August as compared with the remainder of the calendar year (7.2% vs 5.9%, p=0.0178).
  
  
  CONCLUSIONS
  In these studies the diagnosis of oligohydramnios is made more frequently in those pregnancies delivered during the summer months. Although not proven by this association, maternal dehydration may contribute to this finding.
authors.affiliation: Department of Obstetrics and Gynecology, University of Utah, Salt Lake City 84132, USA. mvarner@hsc.utah.edu
authors.forename: Michael W
authors.initials: MW
authors.lastname: Varner
authors.forename: William D
authors.initials: WD
authors.lastname: Noble
authors.forename: Mitchell
authors.initials: M
authors.lastname: Dombrowski
authors.forename: Baha
authors.initials: B
authors.lastname: Sibai
authors.forename: Dwight J
authors.initials: DJ
authors.lastname: Rouse
authors.forename: Richard
authors.initials: R
authors.lastname: Paul
authors.forename: Steve N
authors.initials: SN
authors.lastname: Caritis
authors.forename: Menachem
authors.initials: M
authors.lastname: Miodovnik
authors.forename: Atef
authors.initials: A
authors.lastname: Moawad
authors.forename: Jay D
authors.initials: JD
authors.lastname: Iams
authors.forename: Frank
authors.initials: F
authors.lastname: Witter
authors.forename: Roberto
authors.initials: R
authors.lastname: Romero
authors.forename: Kenneth
authors.initials: K
authors.lastname: Leveno
authors.forename: Paul
authors.initials: P
authors.lastname: Meis
authors.forename: Ronald
authors.initials: R
authors.lastname: Wapner
authors.forename: Mortimer
authors.initials: M
authors.lastname: Rosen
authors.forename: Gary
authors.initials: G
authors.lastname: Thurnau
authors.forename: Peter
authors.initials: P
authors.lastname: van Dorsten
authors.forename: Mary J
authors.initials: MJ
authors.lastname: O'Sullivan
authors.forename: Deborah
authors.initials: D
authors.lastname: Conway
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D016208:Databases, Factual; D005260:Female; D006801:Humans; D008875:Middle Aged; D016104:Oligohydramnios / Q000453:epidemiology* / Q000209:etiology / Q000503:physiopathology; D011247:Pregnancy; D012621:Seasons; D014481:United States / Q000453:epidemiology