Modelling gestational weight gain trajectories and risk of adverse birth outcomes using super imposition by translation and rotation: findings from two Brazilian cohort studies

Summary: Background: Gestational weight gain (GWG) is a key determinant of maternal and neonatal health, yet there are no clear recommendations for tracking GWG trajectories, beyond total amount, in routine care. We aimed to characterise GWG trajectories in terms of both amount and velocity and examine their associations with adverse neonatal outcomes in two Brazilian cohorts, using INTERGROWTH-21st (IG-21st) centiles.