The Effect of Birth Weight on Cognitive Performance: Is There a Social Gradient? Is There Compensation?

Demography has traditionally been interested in birth weight as one of the main indicators of infant health. Specifically, low birth weight (LBW) is known to correlate with adverse health and cognitive outcomes during infancy and adulthood. In this paper we use data from the Chinese Family Panel Study (2010 wave), a large-scale representative sample of Chinese households, to model the effect of LBW on standardized scores among Chinese children aged 10-15. The paper shows a clear gradient in the prevalence of LBW by family background, with children with more socioeconomic resources having higher birth weight and a lower probability of experiencing LBW. Our evidence confirms a significant negative effect of LBW on the results obtained by children in mathematics and Chinese language, two important competences for school success. Our results also imply that highly educated mothers can actually compensate the disadvantage that LBW represents in terms of cognitive performance.