Sleep duration trajectories from age 3 to 48 months in The Pelotas (Brazil) 2004 Birth Cohort Study.

Among the identified trajectories, the group with short sleep duration trajectory deserves special attention given the importance of adequate sleep duration in the first years of life for the child's growth and development and the high concomitance of other risk factors, such as less schooled mothers, and mothers who reported depressive symptoms during pregnancy and consumed alcohol at 3 months post-partum.