**9. Adverse neonatal outcome**

The twin birth study did not found statistically significant difference in morbidity and fetal or neonatal mortality between planned cesarean or planned vaginal delivery [14, 53], and a 2-year follow up after delivery found no difference in neurodevelopment and death in both groups [61].

A retrospective study with 1070 twin pregnancies attempted trial of labor between 2003 and 2015 showed that in planned cesarean, the first twin has a lower blood pH and base excess than in vaginal delivery, but the study was unpowered for neonatal outcome assessment [13].
