title: Discordant lower urinary tract obstruction in early twin gestations: management and outcome.
abstract: OBJECTIVE
  To report our experience with the management of twin pregnancies discordant for lower urinary tract obstruction.
  
  
  METHODS
  Cases of twin pregnancies discordant for lower urinary tract obstruction were identified from our fetal medicine database. Information on ultrasonographic findings, antenatal course, pregnancy complications, and perinatal outcome was obtained by reviewing medical records or contacting the referring obstetricians.
  
  
  RESULTS
  Five twin pregnancies discordant for lower urinary tract obstruction were diagnosed between 11 and 15 weeks of gestation. There were 3 dichorionic and 2 monochorionic pregnancies (1 diamniotic and 1 monoamniotic). The dichorionic pregnancies were managed conservatively, resulting in a pregnancy loss of both twins in 1 case, a single fetal death at 29 weeks in 1 case, and an early neonatal death due to lung hypoplasia of the affected twin in 1 case. On the other hand, both monochorionic twin pregnancies were managed with serial vesicocenteses. In both cases, the prenatal course was complicated, 1 by premature rupture of the membranes and the other by cord entanglement, requiring delivery at 29 and 31 weeks, respectively. Among the 4 continuing pregnancies with complete perinatal outcome, none of the affected twins survived, and the structurally normal twins were delivered between 29 and 36 weeks and discharged from the hospital in good condition.
  
  
  CONCLUSIONS
  Twin pregnancies discordant for lower urinary tract obstruction are at high risk of perinatal death and premature delivery. Prenatal intervention seems not to be associated with an improved perinatal outcome of the affected twin, but it may be beneficial in selected cases to attain viability of the unaffected twin.
authors.affiliation: Fetal Medicine Center, Department of Obstetrics and Gynecology, Clinica Las Condes, Santiago, Chile. fetalmed@yahoo.com
authors.forename: Waldo
authors.initials: W
authors.lastname: Sepulveda
authors.forename: Amy E
authors.initials: AE
authors.lastname: Wong
authors.forename: Juan L
authors.initials: JL
authors.lastname: Alcalde
authors.forename: Victor
authors.initials: V
authors.lastname: Dezerega
authors.forename: Carlos
authors.initials: C
authors.lastname: Barrera
authors.forename: Sergio
authors.initials: S
authors.lastname: de la Fuente
mesh_terms: D004200:Diseases in Twins / Q000151:congenital / Q000175:diagnosis* / Q000628:therapy*; D005260:Female; D005315:Fetal Diseases / Q000175:diagnosis* / Q000628:therapy*; D005865:Gestational Age; D006801:Humans; D011247:Pregnancy; D011256:Pregnancy Outcome; D012189:Retrospective Studies; D016896:Treatment Outcome; D016216:Ultrasonography, Prenatal; D014524:Urethral Obstruction / Q000151:congenital / Q000175:diagnosis* / Q000628:therapy*