title: Donor catch-up growth after laser surgery for twin-twin transfusion syndrome.
abstract: OBJECTIVE
  To assess fetal growth after laser surgery for TTTS at the time of prenatal diagnosis, birth, and at 2years of age.
  
  
  METHODS
  Growth data were collected from surviving children treated between 2007 and 2010 as part of a study to assess neurodevelopment at 24months (±6weeks) corrected age. Fetal weights were obtained via ultrasound using Hadlock's formula at the time of preoperative assessment for laser surgery. Birth weights were recorded by the staff at the delivering institutions. Weights at 2years corrected age were recorded at the time of neurodevelopmental testing. Weights were converted into percentiles according to standard growth curves. Growth restriction was defined as <10th percentile for given age. Multilevel latent growth curve models in Mplus (twins nested in families) examined weight change over time as a function of donor status, and repeated measures ANOVA was utilized to assess in donor-recipient weight discordance over time for twin pairs.
  
  
  RESULTS
  99 of 206 children (56 of 130 families) were studied. There were no differences between enrolled and non-enrolled patients in donor/recipient status and survival rates, fetal demise, intrauterine growth restriction, Quintero stage, and gestational age of surgery or delivery. 48.5% were donors. The median fetal, birth, and 2-year weights for all twins were 288g, 1.9kg, and 11.8kg, respectively, and the overall prevalence of growth restriction was 28%, 22%, and 3%, respectively. Growth restriction rates at prenatal diagnosis were 56% in donors vs. 2% in recipients (OR=64.3, p<0.001); at birth, 35% vs. 10% (OR=5.0, p<0.01); and at 2years, 6% vs. 0%. Donors showed significant gains in weight percentile (B=13.1, p<0.001) and a significant decrease in growth restriction rates over time (B=-1.6, p<0.001). Weight discordance between donor and recipient pairs also significantly decreased over time (linear F(1,42)=54.34, p<0.001).
  
  
  CONCLUSIONS
  After laser surgery for TTTS, donor twins exhibit significant catch-up growth by two years of age.
authors.affiliation: Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, Keck School of Medicine, University of Southern California, United States. Electronic address: chmait@usc.edu.
authors.forename: Ramen H
authors.initials: RH
authors.lastname: Chmait
authors.affiliation: Department of Obstetrics and Gynecology, Kaiser Permanente Los Angeles, CA, United States.
authors.forename: Andrew H
authors.initials: AH
authors.lastname: Chon
authors.affiliation: Division of Hospital Medicine, Children's Hospital Los Angeles, United States.
authors.forename: Sheree M
authors.initials: SM
authors.lastname: Schrager
authors.affiliation: Jackson Fetal Therapy Institute, Jackson Memorial Hospital, Miami, FL, United States.
authors.forename: Eftichia V
authors.initials: EV
authors.lastname: Kontopoulos
authors.affiliation: Jackson Fetal Therapy Institute, Jackson Memorial Hospital, Miami, FL, United States.
authors.forename: Rubén A
authors.initials: RA
authors.lastname: Quintero
authors.affiliation: Department of Pediatrics, Division of General Pediatrics, Keck School of Medicine, University of Southern California, United States.
authors.forename: Douglas L
authors.initials: DL
authors.lastname: Vanderbilt
mesh_terms: D001724:Birth Weight / Q000502:physiology*; D002657:Child Development / Q000502:physiology*; D002675:Child, Preschool; D005260:Female; D047109:Fetal Development / Q000502:physiology*; D020567:Fetal Weight / Q000502:physiology*; D005330:Fetofetal Transfusion / Q000503:physiopathology / Q000601:surgery*; D005865:Gestational Age; D006801:Humans; D053685:Laser Therapy; D008297:Male; D011247:Pregnancy
keywords: Catch-up growth; Growth restriction; Laser surgery; Twin–twin transfusion syndrome