Objective: To 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).
Methods: Electronic 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.
Results: Eleven 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).
Conclusions: The 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.