Sequential vs. Standard Laser Treatment of Twin-twin Transfusion Syndrome

Inclusion criteria

• Gestational age: 16 weeks, 0 days to 26 weeks, 0 days.
• Confirmed TTTS patients, who by definition meet the following sonographic criteria:

• Single placenta.
• Polyhydramnios: maximum vertical pocket ≥ 8 cm in the recipient twin, prior to amniodrainage.
• Oligohydramnios: maximum vertical pocket ≤ 2 cm in the donor twin, prior to amniodrainage.
• Thin dividing membrane (absence of twin peak sign) or absence of dividing membrane (monoamniotic).
• Same gender, if visible.
• Quintero Stages 1-4.
• Patients choosing laser therapy that have undergone prior therapeutic amniocentesis may be included.
• Patients with an anterior placenta may be included.
• Triplet gestations with two or three fetuses sharing the same placenta may be included.
• Patients must be able to give written informed consent.

Exclusion criteria

• Patients unable or unwilling to participate in the study or to be followed up.
• Patients unable to give written informed consent.
• Presence of major congenital anomalies that may not warrant surgery.
• Known unbalanced chromosomal complement.
• Prior intentional septostomy (purposely making a hole in the dividing membrane).
• Ruptured membranes.
• Chorioamnionitis.
• Abnormal intracranial ultrasound findings of either fetus to include, but not limited to: intraventricular hemorrhage, porencephalic cysts, hydrocephalus, Dandy-Walker syndrome, holoprosencephaly and agenesis of the corpus callosum. Isolated ventriculomegaly (atrium 10-19 mm) may or may not be used as exclusion criteria.
• Placental abruption.
• Active labor.
• Patient unwilling to receive blood products.
• Recipient twin with a middle cerebral artery peak systolic velocity > 1.5 multiples of the median (indicative of fetal anemia).
• Any other patient deemed inappropriate for the study by the principal investigator.