To characterize factors associated with adverse neonatal outcomes in prenatally diagnosed omphalocele cases. Prenatally diagnosed omphalocele cases at a single referral center from 1 January 2009 to 31 December 2017 were retrospectively reviewed. Clinical variables and antenatal imaging measurements were collected. Associations between prenatal and neonatal characteristics and the adverse outcome of death or prolonged length of stay (LOS) were analyzed. Out of 63 fetal cases, 33 were live-born, > 50% had other anomalies, and neonatal mortality was 12%. Adverse outcomes were associated with neonatal variables, including lower median 1-min Apgar score, initial mechanical ventilation, and late-onset sepsis, but not approach toomphalocele closure. With multivariate analysis, death or prolonged LOS was associated only with low lung volumes by fetal MRI (OR 34 (3-422), p = 0.006). Low lung volumes by fetal MRI were associated with death or prolonged LOS in neonates with prenatally diagnosed omphalocele and may guide clinicians with counseling families.