ABSTRACTObjectiveTo estimate incidence and risk factors of severe cerebral injury in survivors from monochorionic pregnancies with selective intrauterine growth restriction (sIUGR) and/or birth weight discordance (BWD).MethodsElectronic databases were searched for studies describing perinatal and neurologic outcome in monochorionic twins with sIUGR and/or BWD. Exclusion criteria were twin–twin transfusion syndrome, twin anemia–polycythemia sequence, selective feticide or laser treatment.ResultsEleven articles were included in the systematic review. Analysis was hampered by different methodology and definitions of cerebral injury. The incidence of severe cerebral injury varied from 0% to 33% (average 8%, 52/661), and was higher in studies including single intrauterine demise [odds ratio (OR) 2.92; 95% confidence interval (CI) 0.89‐9.56] and studies with a median gestational age at birth of ≤32 weeks (OR 1.56; 95% CI 1.06–2.27). The risk of severe cerebral injury was higher in pregnancies with abnormal umbilical artery Doppler (13.5% vs 2.5%; OR 7.69; 95% CI 2.56–25.00) and in larger twins (9% vs 5%; OR 1.93; 95% CI 0.95–3.92).ConclusionsThe incidence of severe cerebral injury in monochorionic twins with sIUGR and/or BWD is approximately 8% and is associated with abnormal umbilical artery Doppler, larger twins, intrauterine fetal demise and low gestational age at birth. © 2013 John Wiley & Sons, Ltd.