title: Postnatal survival after endoscopic equatorial laser for the treatment of twin-to-twin transfusion syndrome.
abstract: BACKGROUND
  Endoscopic laser coagulation of placental anastomoses is the first-line treatment for severe twin-to-twin transfusion syndrome. A recent randomized controlled trial reported that laser coagulation along the entire vascular equator was associated with a similar dual survival and survival of at least 1 twin compared with the group that was treated with the selective technique. In addition, there was a significantly lower incidence of postoperative recurrence of twin-to-twin transfusion syndrome and the development of twin anemia-polycythemia sequence in the equatorial group.
  
  
  OBJECTIVE
  The purpose of this study was to report on neonatal survival in twin-to-twin transfusion syndrome pregnancies that were treated with endoscopic laser therapy with the use of the equatorial technique and to examine the relationship between preoperative factors and twin loss.
  
  
  METHODS
  Endoscopic equatorial laser therapy was carried out as the primary treatment for twin-to-twin transfusion syndrome in all consecutive monochorionic diamniotic twin pregnancies that were referred at a single fetal surgery Center over a 4-year period. All visible placental anastomoses were coagulated; additional laser ablation of the placental tissue between the coagulated vessels was carried out. Pre-laser ultrasound data, periprocedural complications, pregnancy outcome, and postnatal survival at hospital discharge were recorded and analyzed.
  
  
  RESULTS
  A total of 106 pregnancies were treated during the study period. Median gestational age at laser therapy was 19.7 weeks (range, 15.1-27.6 weeks). There was postoperative recurrence of twin-to-twin transfusion syndrome or the development of twin anemia-polycythemia sequence in 2 (1.9%) and 2 (1.9%) cases, respectively. The survival rates of both and at least 1 twin were 56.6% and 83.0%, respectively. Donor survival was significantly lower compared with the recipient co-twin (64.2% vs 75.5%, respectively; P < .05). The rate of fetal death, which was the most common cause of twin loss, was significantly higher in donors compared with recipient fetuses (23.6% vs 10.4%, respectively; P < .05). In cases with absent or reversed end-diastolic velocity in the donor umbilical artery, dual and donor survival rates were significantly lower compared with the remaining twin-to-twin transfusion syndrome pregnancies (40.0% vs 64.8% and 40.0% vs 76.1%, respectively; P < .05). There were no significant differences between the 2 groups in the survival of at least 1 twin and in the recipient survival.
  
  
  CONCLUSIONS
  Endoscopic equatorial laser therapy was associated with a survival of both and at least 1 twin of approximately 55% and 83%, respectively, with a low rate of recurrent twin-to-twin transfusion syndrome and twin anemia-polycythemia sequence. In addition, the preoperative finding of abnormal donor umbilical artery Doppler on ultrasound identified a subgroup of twin-to-twin transfusion syndrome pregnancies with a lower dual survival rate caused by increased intrauterine deaths of donor twins.
authors.affiliation: Department of Obstetrics and Gynecology 'L. Mangiagalli', Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy. Electronic address: nicola.persico@gmail.com.
authors.forename: Nicola
authors.initials: N
authors.lastname: Persico
authors.affiliation: Department of Obstetrics and Gynecology 'L. Mangiagalli', Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy.
authors.forename: Isabella
authors.initials: I
authors.lastname: Fabietti
authors.affiliation: Department of Obstetrics and Gynecology 'L. Mangiagalli', Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: D'Ambrosi
authors.affiliation: Department of Obstetrics and Gynecology 'L. Mangiagalli', Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy.
authors.forename: Maria
authors.initials: M
authors.lastname: Riccardi
authors.affiliation: Department of Obstetrics and Gynecology 'L. Mangiagalli', Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy.
authors.forename: Simona
authors.initials: S
authors.lastname: Boito
authors.affiliation: Department of Obstetrics and Gynecology 'L. Mangiagalli', Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: Fedele
mesh_terms: D000740:Anemia / Q000150:complications; D004200:Diseases in Twins / Q000150:complications; D005260:Female; D005330:Fetofetal Transfusion / Q000401:mortality* / Q000601:surgery*; D005332:Fetoscopy; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D017075:Laser Coagulation; D016015:Logistic Models; D010920:Placenta / Q000098:blood supply / Q000601:surgery; D011086:Polycythemia / Q000150:complications; D011247:Pregnancy; D012008:Recurrence; D018608:Ultrasonography, Doppler; D014469:Umbilical Arteries / Q000000981:diagnostic imaging
keywords: Doppler assessment; equatorial laser therapy; monochorionic diamniotic twins; survival; twin-to-twin transfusion syndrome