Intensive management and early delivery reduce antenatal mortality in monoamniotic twin pregnancies

Background: Intensive management and elective delivery between 32 and 35 weeks of monoamniotic twin pregnancies were suggested as improving perinatal outcome. We sought to evaluate this management as viewed by the outcome of monoamniotic twin pregnancies in our population. Methods: A retrospective systematic chart review of all monoamniotic twin pregnancies, diagnosed from January 1986 to June 2002, was performed in three medical centers. Demographics, pregnancy course, and perinatal outcome were evaluated. The management and outcome were compared between the group of survivors and the groups of intrauterine fetal demise (IUFD) and miscarriage. Results: Thirty-three pairs of monoamniotic twins were identified. Excluded were three women, who chose to terminate the pregnancy. Total survival rate was 60% (of 60 fetuses, 36 were born alive, but one neonate died due to sepsis). None of the IUFD occurred in hospitalized patients, and two pairs of twins died after 32 weeks. In the 10 twin pairs who died in utero, cord entanglement was documented in eight (80%). There were two cases of twin discordance and two cases of twin-to-twin transfusion syndrome. One twin of the live-born group had congenital transposition of the great arteries. Furthermore, one of the hospitalized patients was delivered by means of an emergency cesarean section because of a non-reassuring non-stress test at 30 weeks. Conclusions: Women with monoamniotic twin pregnancies should be advised about the very high mortality and morbidity rate. Early diagnosis, close in-hospital antenatal surveillance starting at fetal viability, and elective delivery at 32 weeks would reduce the antenatal mortality.