This is a study to compare two treatments (amnioreduction vs. selective fetoscopic laser photocoagulation [SFLP]) in patients with severe twin to twin transfusion syndrome.

We hypothesize that treatment of the underlying chorioangiopagus by selective fetoscopic laser photocoagulation will not only improve the survival of twins but will reduce the incidence of neurologic, cardiac, and developmental sequelae of twin-twin transfusion syndrome (TTTS). We propose to test this hypothesis by a prospective randomized multicenter trial to compare serial amnioreduction with selective fetoscopic laser photocoagulation in cases of severe (stage II-IV) twin-twin transfusion syndrome (TTTS). Primary Outcomes: Survival of donor twin at 30 days after birth and no treatment failure; Survival of recipient twin at 30 days after birth and no treatment failure; Secondary Outcomes: Survival times of each twin in utero or after birth (which may be censored at 30 days after birth); Gestational age at delivery; Placental insufficiency; Cardiac outcome: echocardiographic evidence of cardiac compromise; Neurologic outcome: evidence of brain injury preceding birth by MRI; Postnatal comorbidity

Inclusion Criteria:

• Both twins are alive
• TTTS diagnosed prior to 22 weeks gestation
• Monochorionic diamniotic gestation
• Like sex twins
• Single placental mass
• Thin intertwin membrane
• Oligohydramnios in donor twin (deepest vertical pocket of ≤ 2 cm)
• Polyhydramnios with deepest vertical pocket of > 8 cm with or without Doppler or echocardiographic changes in the recipient twin (deepest vertical pocket of > 6 cm if previous amnioreduction)
• Decompressed bladder in donor not seen to fill during the ultrasound examination (stage II, III, or IV), unless Doppler velocimetry changes (absent end-diastolic umbilical artery flow, abnormal ductus venosus waveform), and/or echocardiographic changes (valvular insufficiency, ventricular hypertrophy) are already present
• No associated structural abnormalities
• No sonographic evidence of CNS injury at time of entry
• No preterm labor
• No maternal medical contraindication to anesthesia or surgery

Exclusion Criteria:

• Failure to meet all inclusion criteria
• TTTS presenting after 22 weeks gestation
• Randomization after 24 weeks gestation
• Cervical length < 2.0 cm post initial
• Presence of cervical cerclage
• Uterine anomaly
• Refusal to accept randomization
• Unable to pursue prenatal care at an approved center coordinated by one of the participating institutions
• Unable to pursue postnatal evaluation at a NICHD Neonatal Research Network Institution