Perinatal outcome of monochorionic in comparison to dichorionic twin pregnancies

Objective: The aim of this study is to compare the neonatal outcomes of monochorionic and dichorionic twin pregnancies. Methods: A retrospective cohort study involving 51 twin pregnancies followed and delivered at Sultan Qaboos University Hospital was conducted between January 2006 and December 2011. Result: Thirty six (71%) pregnancies were dichorionic diamniotic (DCDA), 14 (27%) were monochorionic diamniotic (MCDA), and one (2%) was monochorionic monoamniotic (MCMA). The antepartum complications noted in the 15 monochorionic twins were discordant fetal growth in 2 (14%) cases, low birth weight in 11 (73%) babies, pre-eclampsia in three mothers (21%) and twin to twin transfusion syndrome in four (29%) cases. Fetal respiratory distress affected eight (57%) of the pregnancies. Six (40%) twin sets were delivered before 30 weeks, 4 (27%) sets at 31 to 32 weeks, 2 (13%) sets at 34-35 weeks, 2 (13%) sets at 36-37 weeks, and 1 (7%) at 37-38 weeks. Fifteen mothers delivered 16 live infants, 9 (30%) stillbirths and 5 (17%) died after birth. Most neonatal deaths were due to neonatal sepsis and pulmonary hypoplasia. Dichorioinic twins, (DC) morbidity was seen in 11% and 40% for monochoroinic twins (MC). Mortality rate was 17% for DC and 47% for MC twins. Conclusions: Perinatal morbidity and mortality remain high among monochorionic twins. This is likely due to frequent twin-to-twin transfusion syndrome, prematurity, fetal growth restriction and intrauterine fetal death. Improved fetal and neonatal management may result in improved outcomes.