Curado J, et al. - This study was undertaken to investigate the natural history and outcome of selective fetal growth restriction (sFGR) in monochorionic diamniotic (MCDA) twin pregnancy, according to gestational age at onset and various reported diagnostic criteria, and to quantify the risk of superimposed twin‐to‐twin transfusion syndrome (TTTS). A cohort study was designed to include MCDA twin pregnancies that had their routine antenatal care from the first trimester at St George's Hospital, London, UK. Researchers calculated the diagnostic criteria for sFGR fetal weight (EFW) of one twin < 10th centile and intertwin EFW discordance ≥ 25%. Study compared the incidence of sFGR between the different diagnostic criteria, overall and according to gestational age at onset. A total of 287 MCDA twin pregnancies were included in the analysis. Although this difference was not significant, and is correlated with worse perinatal outcome, early‐onset sFGR is slightly more common than is late‐onset sFGR in MCDA twin pregnancies. The study found higher incidence of Types II and III sFGR in early‐onset sFGR. According to the diagnostic criteria used, the incidence also varies, which supports the use of standardized international diagnostic criteria. Compared with late‐onset sFGR, superimposed TTTS is more common in early‐onset sFGR.