title: Vasa previa: clinical presentations, outcomes, and implications for management.
abstract: OBJECTIVE
  To review experience with diagnosis, clinical associations, and outcomes of vasa previa in a single institution.
  
  
  METHODS
  This was a retrospective review of all identified vasa previa cases from January 1 1990, to June 30, 2010.
  
  
  RESULTS
  Sixty cases of vasa previa were identified (53 singletons, seven twins); 56 cases were diagnosed before delivery. An abnormal cord insertion or abnormal placental location was present in 55 cases. Missed diagnoses were attributed to technical and observer factors. Preterm bleeding was encountered in 25 (42%) case group participants. Seven case group participants required an emergent delivery, with significant neonatal morbidity and mortality. Twin pregnancies had a significantly earlier median age at delivery of 32 weeks of gestation compared with 35 weeks of gestations in singletons (P=.01). The seven twin pregnancies had a 28.6% emergent preterm delivery rate, whereas singletons had a 4.1% rate (P=.07). In 14 case group participants, the membranous fetal vessel was located in the lower uterus and not directly over the cervix. The vessel location was not related to the risk of emergent delivery.
  
  
  CONCLUSIONS
  Transvaginal ultrasound scans of at-risk patients can identify most cases of vasa previa. Preterm bleeding does not usually require immediate delivery. The rate of emergent preterm delivery was low in singleton pregnancies. Twins were delivered, on average, 3 weeks earlier than singletons.
  
  
  METHODS
  III.
authors: Department of Obstetrics and Gynecology and Research Institute, William Beaumont Hospital, Royal Oak, Michigan; and the Departments of Obstetrics and Gynecology, Wayne State University, Detroit, Michigan, Baylor College of Medicine, Houston, Texas, and the University of Rochester, Rochester, New York.
authors: Richard
authors: R
authors: Bronsteen
authors: Amy
authors: A
authors: Whitten
authors: Mamtha
authors: M
authors: Balasubramanian
authors: Wesley
authors: W
authors: Lee
authors: Robert
authors: R
authors: Lorenz
authors: Mark
authors: M
authors: Redman
authors: Luis
authors: L
authors: Goncalves
authors: David
authors: D
authors: Seubert
authors: Sam
authors: S
authors: Bauer
authors: Christine
authors: C
authors: Comstock
mesh_terms: D036861:Delivery, Obstetric / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008824:Michigan / Q000453:epidemiology; D011247:Pregnancy; D059285:Pregnancy, Twin; D012189:Retrospective Studies; D016216:Ultrasonography, Prenatal; D055949:Vasa Previa / Q000000981:diagnostic imaging* / Q000453:epidemiology
references: Oyelese Y, Catanzarite V, Prefumo F, Lashley S, Schachter M, Tovbin Y, et al.. Vasa previa: the Impact of prenatal diagnosis on outcome. Obstet Gynecol 2004;103:937–42.
references: Catanzarite V, Maida C, Thomas W, Mendoza A, Stanco L, Piacquadio KM. Prenatal sonographic diagnosis of casa previa: ultrasound findings and obstetric outcome in ten cases. Ultrasound Obstet Gynecol 2001;18:109–15.
references: Baulies S, Maiz N, Muñoz A, Torrents M, Echevarría M, Serra B. Prenatal ultrasound diagnosis of vasa praevia and analysis of risk factors. Prenat Diagn 2007;27:595–9.
references: Cipriano LE, Barth WH Jr, Zaric GS. The cost-effectiveness of targeted or universal screening for vasa praevia at 18-20 weeks of gestation in Ontario. BJOG 2010;117:1108–18.
references: Oyelese KO, Turner M, Lees C, Campbell S. Vasa previa: an avoidable obstetric tragedy. Obstet Gynecol Surv 1999;54:138–45.
references: Smorgick N, Tovbin Y, Ushakov F, Vaknin Z, Barzilay B, Herman A, et al.. Is neonatal risk from vasa previa preventable? The 20-year experience from a single medical center. J Clin Ultrasound 2010;38:118–22.
references: Sepulveda W, Rojas I, Robert JA, Schnapp C, Alcalde JL. Prenatal detection of velamentous insertion of the umbilical cord: a prospective color Doppler ultrasound study. Ultrasound Obstet Gynecol 2003;21:564–9.
references: Schachter M, Tovbin Y, Arieli S, Friedler S, Ron-El R, Sherman D. In vitro fertilization is a risk factor for vasa previa. Fertil Steril 2002;78:642–3.
references: Lee W, Lee VL, Kirk JS, Sloan CT, Smith RS, Comstock CH. Vasa previa: prenatal diagnosis, natural evolution, and clinical outcome. Obstet Gynecol 2004;95:572–6.
references: Fung TY, Lau TK. Poor perinatal outcome associated with vasa previa: is it preventable? A report of three cases and review of the literature. Ultrasound Obstet Gynecaol 1998;12:430–3.
references: Ioannou C, Wayne C. Diagnosis and management of vasa previa: a questionnaire survey. Ultrasound Obstet Gynecol 2010;35:205–9.
references: Oyelese Y, Smulian JC. Placenta previa, placenta accreta, and vasa previa. Obstet Gynecol 2006;107:927–41.