title: Second trimester amniotic fluid is reliably fern positive and α1-microglobulin positive: dispelling a labor deck myth.
abstract: OBJECTIVE
  Many physicians erroneously believe and have propagated the "myth" that a second trimester amniotic fluid sample will not fern. We attempted to redemonstrate ferning and to demonstrate the efficacy of an assay for α1-microglobulin in second trimester amniotic fluid samples.
  
  
  METHODS
  Amniotic fluid samples were collected from women undergoing routine genetic amniocentesis between 15 and 26 weeks. A total of 97 samples of second trimester amniotic fluid were placed on slides and examined for ferning at 5 and 10 minutes. An α1-microglobulin assay was performed on each sample. Data were recorded and reported.
  
  
  RESULTS
  Approximately 93% of samples were fern positive at 5 minutes and 100% were fern positive at 10 minutes. All samples were α1-microglobulin positive.
  
  
  CONCLUSIONS
  Pure amniotic fluid is reliably fern and α1-microglobulin positive in the second trimester. Republication of data only available in pre-online sources will benefit physicians and patients.
authors.affiliation: Division of Female Pelvic and Reconstructive Surgery, Department of Obstetrics and Gynecology, Emory University School of Medicine, Atlanta, Georgia.
authors.forename: Nicholas S
authors.initials: NS
authors.lastname: Fogelson
authors.affiliation: Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Georgia Health Sciences University, Augusta, Georgia.
authors.forename: Paul C
authors.initials: PC
authors.lastname: Browne
authors.affiliation: Department of Obstetrics and Gynecology, University of South Carolina School of Medicine, Columbia, South Carolina.
authors.forename: Stanette
authors.initials: S
authors.lastname: Browne
authors.affiliation: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, University of Florida School of Medicine, Gainesville, Florida.
authors.forename: Anthony R
authors.initials: AR
authors.lastname: Gregg
mesh_terms: D000328:Adult; D000510:Alpha-Globulins / Q000032:analysis*; D000649:Amniocentesis; D000653:Amniotic Fluid / Q000737:chemistry* / Q000502:physiology; D005260:Female; D005322:Premature Rupture of Fetal Membranes / Q000175:diagnosis*; D006801:Humans; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D012680:Sensitivity and Specificity
chemical_list: D000510:Alpha-Globulins; C025734:chorionic alpha(1)-microglobulin