title: Prediction of single fetal demise after laser therapy for twin-twin transfusion syndrome.
abstract: OBJECTIVE
  Single fetal demise (SFD) occurs in up to 20% of monochorionic pregnancies treated with laser coagulation for twin-twin transfusion syndrome (TTTS). We aimed to determine the independent factors associated with SFD to improve outcome in the care of TTTS pregnancies in the future.
  
  
  METHODS
  This was a case-control study on twin pregnancies treated for TTTS between 2007 and 2013. Data on ultrasound, laser surgery and outcome were retrieved from our monochorionic twin database. We analyzed separately cases of SFD in donor and recipient twins, and compared them with treated pregnancies that resulted in two live births.
  
  
  RESULTS
  Of the 273 TTTS pregnancies treated with laser coagulation, SFD occurred in 30 donors (11.0%) and 27 recipients (9.9%). In 67% of pregnancies with SFD, the death occurred within 1 week after laser treatment. For SFD in donors, absent/reversed end-diastolic flow in the umbilical artery was the strongest predictor (odds ratio (OR), 3.0 (95% CI, 1.1-8.0); P = 0.01), followed by the presence of an arterioarterial anastomosis (OR, 4.2 (95% CI, 1.4-13.1); P = 0.03) and discordance in estimated fetal weight (OR, 1.0 (95% CI, 1.0-1.1); P = 0.04). For SFD in recipients, independent predictors were absent/reversed A-wave in the ductus venosus (OR, 3.6 (95% CI, 1.2-10.5); P = 0.02) and the absence of recipient-to-donor arteriovenous anastomoses (OR, 10.6 (95% CI, 1.8-62.0); P < 0.01).
  
  
  CONCLUSIONS
  Our findings confirm earlier reports that suggest that abnormal blood flow is associated with SFD after laser treatment for TTTS. The association of SFD with the type of anastomoses is a new finding. We speculate that the type of anastomoses present determines the degree of hemodynamic change during laser therapy. Future strategies should aim at stabilizing fetal circulation before laser therapy to decrease the vulnerability to acute preload and afterload changes. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.
authors.affiliation: Department of Obstetrics, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: S J
authors.initials: SJ
authors.lastname: Eschbach
authors.affiliation: Department of Obstetrics, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: L S T M
authors.initials: LS
authors.lastname: Boons
authors.affiliation: Department of Medical Statistics, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: R
authors.initials: R
authors.lastname: Wolterbeek
authors.affiliation: Department of Obstetrics, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: J M
authors.initials: JM
authors.lastname: Middeldorp
authors.affiliation: Department of Obstetrics, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: F J C M
authors.initials: FJ
authors.lastname: Klumper
authors.affiliation: Department of Pediatrics, Division of Neonatology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: E
authors.initials: E
authors.lastname: Lopriore
authors.affiliation: Department of Obstetrics, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: D
authors.initials: D
authors.lastname: Oepkes
authors.affiliation: Department of Obstetrics, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: M C
authors.initials: MC
authors.lastname: Haak
mesh_terms: D001783:Blood Flow Velocity / Q000502:physiology; D016022:Case-Control Studies; D005260:Female; D005313:Fetal Death / Q000517:prevention & control*; D005330:Fetofetal Transfusion / Q000401:mortality / Q000628:therapy*; D005865:Gestational Age; D006801:Humans; D017075:Laser Coagulation / Q000009:adverse effects*; D053685:Laser Therapy / Q000009:adverse effects*; D010920:Placenta / Q000098:blood supply / Q000601:surgery; D011247:Pregnancy; D011256:Pregnancy Outcome; D018607:Pregnancy Reduction, Multifetal; D012307:Risk Factors; D014430:Twins, Monozygotic
keywords: anastomoses; laser therapy; prediction; single fetal demise; syndrome; twin-twin transfusion