Managing Monoamniotic Twin Pregnancies

Monoamniotic twins comprise a rare but important subset of twins at risk of unique and serious complications, placing them at the highest risk of perinatal mortality of all twin gestations. In addition to risks faced by all twins (prematurity, selective growth restriction), all monochorionic twins (twin-twin transfusion syndrome), and all monozygotic twins (congenital anomalies), monoamniotic twins face the unique risk of cord entanglement. Accordingly, early diagnosis, screening for fetal anomalies, surveillance for twin-twin transfusion syndrome, decisions related to monitoring after viability, and timing and route of delivery are all critical. Herein, we present recommendations for optimal management.