Randomized Clinical Trial: Expectant Management vs Laser Treatment of Monochorionic Twins With Severe Selective Intrauterine Growth Retardation and Absent or Reverse Diastolic Flow in the Umbilical Artery

University of South Florida

Status: Completed

Conditions: Intrauterine Growth Retardation

Treatments: Device: Expected Management; Procedure: selective laser photocoagulation of communicating vessels

Study type: Interventional

Funder types: Other

Identifiers

NCT01177553

IRB#105690

Details and patient eligibility

About

Intrauterine growth retardation (IUGR) occurs in approximately 3 to 10% of singleton pregnancies, in 9.1% of all twins and 9.9% of monochorionic twins. IUGR in monochorionic twins typically affects only one of the fetuses (selective IUGR or SIUGR). Spontaneous demise of the SIUGR twin can occur, and may result in concomitant demise (up to 40% risk) or severe neurologic handicap (up to 30% risk) of the other twin. These complications result from exsanguination of the appropriately grown (AGA) twin into the demised SIUGR twin through placental vascular communications.

Because the adverse effects to the AGA twin of the spontaneous demise of the SIUGR twin are mediated through placental vascular anastomoses, we have proposed obliterating such anastomoses via endoscopic fetal surgery. We have developed a technique that allows us to identify the vascular anastomoses present in monochorionic placentas. Briefly, deep AV communications are identified on the surface of the placenta by noting that the terminal end of the artery of one of the fetuses does not have a corresponding returning vein to the same fetus. We have speculated that the separation of the circulations may be of benefit in monochorionic twins affected by SIUGR by preventing the adverse effects that may result from the spontaneous demise of the IUGR twin. Our goal is to evaluate with a randomized clinical trial the outcome of SIUGR managed either expectantly or with SLPCV.

Study procedures will begin with confirmation of the diagnosis and screening criteria at the Qualified Clinical Center. The patient will sign the appropriate consents and then be randomized to her treatment group. Enrollment data will be submitted to the research coordinator in Coordinating Center in Tampa. Expectant management patients will be treated by the referring physicians. Laser patients will be treated at Coordinating Center in Tampa General Hospital or qualified laser center. They may return to the referring center for follow-up. After delivery, outcome data will be sent to the research coordinator in Coordinating Center in Tampa.

Enrollment: 5 patients

Sex: Female

Ages: 18 to 55 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Gestational age 16--24 weeks
• Sonographic evidence of monochorionicity: single placenta, same gender, absent twin-peak sign
• Diagnosis of IUGR present in one twin (fetal weight at or below the 10th percentile for gestational age)
• Persistent absent or reverse-end diastolic flow in the umbilical artery in the SIUGR twin
• Able to provide written informed consent

Exclusion criteria

• Patients unwilling to participate in the study, provide consent, or to be followed up
• Presence of twin-twin transfusion syndrome (TTTS) defined as a maximum vertical pocket (MVP) of ≤2 cm in one sac and MVP of ≥8 cm in the other sac.
• Presence of major congenital anomalies (anencephaly, acardia, spina bifida) or intracranial findings in either twin: IVH, porencephalic cysts, ventriculomegaly or other findings suggestive of brain damage.
• Both twins are <10th percentile
• Diastolic flow or intermittently absent end-diastolic flow in the umbilical artery in the SIUGR twin
• Unbalanced chromosomal complement (if known).
• Ruptured or detached membranes
• Placental abruption
• Chorioamnionitis
• Triplets
• Active labor
• Jehovah's witness
• Any other patient deemed inappropriate for the study by the principal investigator
• Placenta previa

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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5 participants in 2 patient groups

Surgery Group

Active Comparator group

Description:

Patients randomized to surgery will have hospital arrangements (laboratory tests and anesthesia assessment) finalized for a surgery the next day. Patients will sign the informed consent form. Patients undergoing surgery will be admitted to Tampa General Hospital and will complete usual hospital admission procedures.

Treatment:

Procedure: selective laser photocoagulation of communicating vessels

Expectant Management Group

Active Comparator group

Description:

Patients randomized to expectant management will be referred back to their referring obstetrician of perinatologist and advised to undergo weekly ultrasound examinations including Doppler studies of the umbilical artery and amniotic fluid volume. Fetal growth will be assessed every 2-4 weeks. After 24 weeks patients may undergo frequent ultrasound examinations or fetal heart rate monitoring to assess fetal well being. These ultrasounds will be performed by the patient's perinatologist or obstetrician, and will be reported to the research team on an ongoing basis throughout the pregnancy.

Treatment:

Device: Expected Management