Abstract

OBJECTIVE: Twin pregnancies are associated with increased perinatal mortality and morbidity, but long-term neurodevelopmental outcomes remain under-investigated. The primary objective was to investigate the incidence of adverse neurodevelopment after one year of age in complicated monochorionic diamniotic (MCDA) twin pregnancies compared with uncomplicated twin pregnancies. METHODS: This was a prospective cohort study conducted at St George's University Hospital NHS Foundation Trust, London. Women with twin pregnancies culminating in at least one child surviving to at least 12 months up to 60 months (corrected for prematurity) at the time of assessment, were invited to complete the relevant Ages and Stages Questionnaires® test version 3 (ASQ-3). The two study groups were (1) complicated MCDA twin pregnancies and uncomplicated twin pregnancies (dichorionic and MCDA). Complicated twin pregnancies included those with twin-to-twin transfusion syndrome (TTTS), Twin Anaemia Polycythaemia Sequence (TAPS), selective Fetal Growth Restriction (sFGR), Twin Reversed Arterial Perfusion (TRAP) and single intrauterine demise (sIUD).  The primary outcome measure was an abnormal ASQ-3 score, defined as a score of 2 standard deviations below the mean, for any one domain. Mixed-effects multivariable logistic regression was performed to determine whether a complicated MCDA twin pregnancy was independently associated with an abnormal ASQ-3 score. All analyses were performed using R v4.0 (R Foundation for Statistical Computing, Vienna, Austria) RESULTS: The study included 174 parents who completed the questionnaires, and therefore, 327 ASQ-3 questionnaires were available for analysis. Of those, 117/327 (35.8%) were classified as cases and 210/327 (64.2%) as controls. The overall incidence of an abnormal ASQ-3 score in children with complicated MCDA twin pregnancies was nearly double that in uncomplicated MCDA/DCDA twin pregnancies (14.5% versus 7.6%, p=0.056). Children born of complicated MCDA twin pregnancies showed significantly higher gross motor domain impairment rates than the control group (8.5% versus 2.9%, p=0.022). Complicated MCDA twin pregnancies that underwent prenatal intervention had significantly higher rates of abnormal ASQ-3 scores compared to those that did not have any prenatal intervention (28.1% versus 1.7%, p=0.0001). On multilevel logistic regression analysis, complicated MCDA twin pregnancy was an independent predictor of abnormal ASQ-3 score in one or more domains (OR: 3.28 (95% CI: 3.27-3.29; p<0.001). CONCLUSION: This study provides evidence that survivors of complicated MCDA twin pregnancies have a higher rate of adverse neurodevelopmental outcomes, independent of prematurity. Long-term neurodevelopmental follow-up in these pregnancies can ensure optimal timely management of those affected. This article is protected by copyright. All rights reserved.