Hiersch L, Barrett J, Aviram A, et al. - Researchers conducted a retrospective cohort study of women with twin pregnancies in a single tertiary referral center with the aim to determine distinct patterns of discordant fetal growth in twin pregnancies. In addition, they assessed if these patterns are predictive of adverse pregnancy outcomes. During the study period, they identified a total of 2,075 women with a twin gestation; the study criteria were met by 1,059 of these. Classification of 599 (57%) as no significant discordance (Pattern 1), 23 (2%) as early progressive discordance (Pattern 2), 160 (15%) as early discordance with plateau (Pattern 3), and 277 (26%) as late discordance (Pattern 4) was done. Overall 4 distinct discordance growth patterns were identified among twins that exhibited a dose-response relationship with adverse outcomes, and appear to be more informative than a single measurement of size discordance.