title: Labor and membrane rupture in twin gestation. Can they affect the ability to estimate fetal weight?
abstract: OBJECTIVE
  To determine whether labor or fetal membrane rupture adversely affects the ability of ultrasound to accurately estimate fetal weight (EFW) in a twin gestation.
  
  
  METHODS
  A medical record audit was performed of the two-year experience of women delivering live born twins and undergoing a complete ultrasound examination within 72 hours of delivery. Those patients experiencing labor or membrane rupture at the time of the previous ultrasound examination were compared to those without these factors to determine if there was any detrimental impact on the accuracy of ultrasound to EFW.
  
  
  RESULTS
  The overall ability of ultrasound to accurately EFW was in the range of 64-76%. This was not significantly different from the accuracy in women experiencing labor (62-80%) or in women with membrane rupture (63-81%). The ability of ultrasound to detect fetal discordance is this series ranged from 78% to 100%, with specificity that ranged from 84% to 89%.
  
  
  CONCLUSIONS
  The ability of sonography to accurately EFW as well as detect discordant twin gestation is not altered by the presence of labor or membrane rupture.
authors.affiliation: Department of Obstetrics and Gynecology, University of Mississippi Medical Center, 2500 North State Street, Jackson, MS 39216-4505, USA.
authors.forename: W E
authors.initials: WE
authors.lastname: Roberts
authors.forename: E C
authors.initials: EC
authors.lastname: Gnam
authors.forename: E F
authors.initials: EF
authors.lastname: Magann
authors.forename: J N
authors.initials: JN
authors.lastname: Martin
authors.forename: J C
authors.initials: JC
authors.lastname: Morrison
mesh_terms: D000328:Adult; D005321:Extraembryonic Membranes / Q000502:physiology*; D005260:Female; D020567:Fetal Weight; D005865:Gestational Age; D006801:Humans; D007743:Labor, Obstetric; D011247:Pregnancy; D011272:Pregnancy, Multiple; D012680:Sensitivity and Specificity; D014427:Twins; D016216:Ultrasonography, Prenatal