title: Amniotic fluid "sludge" is an independent risk factor for preterm delivery.
abstract: OBJECTIVE
  To determine the prevalence and the clinical significance of amniotic fluid "sludge" (AFS) in asymptomatic patients at low and high risk for spontaneous preterm delivery.
  
  
  METHODS
  A prospective cohort study was conducted on 195 singleton pregnancies at low or high risk for preterm birth (PTB) between the 16th and 26th weeks. Cervical length (CL) <25 mm and the presence of AFS were evaluated. The risk for preterm delivery before 28, 32, 35 and 37 weeks were determined according to the presence of AFS, CL < 25 mm and history of high risk for PTB. Stepwise logistic regression was performed to compare variables.
  
  
  RESULTS
  AFS was an independent risk factor for PTB < 35 weeks (OR: 3.08, 95% CI: 1.13-8.34, p = 0.027) but not for PTB < 28, 32 and 37 weeks. CL < 25 mm was an independent risk factor for PTB < 28, 32 and 35 but not for PTB < 37 weeks. High risk for PTB was not found as an independent risk factor for PTB.
  
  
  CONCLUSIONS
  AFS is an independent risk factor for PTB before 35 weeks.
authors.affiliation: a Department of Obstetrics , Paulista School of Medicine, Federal University of Sao Paulo (EPM-UNIFESP) , São Paulo , Brazil.
authors.forename: Alan Roberto
authors.initials: AR
authors.lastname: Hatanaka
authors.affiliation: a Department of Obstetrics , Paulista School of Medicine, Federal University of Sao Paulo (EPM-UNIFESP) , São Paulo , Brazil.
authors.forename: Rosiane
authors.initials: R
authors.lastname: Mattar
authors.affiliation: a Department of Obstetrics , Paulista School of Medicine, Federal University of Sao Paulo (EPM-UNIFESP) , São Paulo , Brazil.
authors.forename: Tatiana Emy Nishimoto
authors.initials: TE
authors.lastname: Kawanami
authors.affiliation: a Department of Obstetrics , Paulista School of Medicine, Federal University of Sao Paulo (EPM-UNIFESP) , São Paulo , Brazil.
authors.forename: Marcelo Santucci
authors.initials: MS
authors.lastname: França
authors.affiliation: a Department of Obstetrics , Paulista School of Medicine, Federal University of Sao Paulo (EPM-UNIFESP) , São Paulo , Brazil.
authors.forename: Liliam Cristine
authors.initials: LC
authors.lastname: Rolo
authors.affiliation: a Department of Obstetrics , Paulista School of Medicine, Federal University of Sao Paulo (EPM-UNIFESP) , São Paulo , Brazil.
authors.forename: Roseli Mieko Yamamoto
authors.initials: RM
authors.lastname: Nomura
authors.affiliation: a Department of Obstetrics , Paulista School of Medicine, Federal University of Sao Paulo (EPM-UNIFESP) , São Paulo , Brazil.
authors.forename: Edward
authors.initials: E
authors.lastname: Araujo Júnior
authors.affiliation: a Department of Obstetrics , Paulista School of Medicine, Federal University of Sao Paulo (EPM-UNIFESP) , São Paulo , Brazil.
authors.forename: Luciano Marcondes Machado
authors.initials: LM
authors.lastname: Nardozza
authors.affiliation: a Department of Obstetrics , Paulista School of Medicine, Federal University of Sao Paulo (EPM-UNIFESP) , São Paulo , Brazil.
authors.forename: Antonio Fernandes
authors.initials: AF
authors.lastname: Moron
mesh_terms: D000328:Adult; D000653:Amniotic Fluid / Q000000981:diagnostic imaging*; D001938:Brazil / Q000453:epidemiology; D005260:Female; D006801:Humans; D011247:Pregnancy; D047928:Premature Birth / Q000453:epidemiology*; D011446:Prospective Studies; D012307:Risk Factors; D014463:Ultrasonography; D055815:Young Adult
keywords: Amniotic fluid “sludge”; cervical length measurement; chorioamnionitis; inflammation; premature birth; ultrasonography