Association of education and the occurrence of low birthweight in rural southern China during the early and late 1990s

Objectives. We examined whether education-related inequalities were associated with the occurrence of low birthweight in 6 counties in southern China in the early and late 1990s. Methods. The study population consisted of 111181 women (65669 in the early 1990s and 45482 in the late 1990s) in a population-based Perinatal Health Care Surveillance System. We used the χ2 test, logistic regression, and concentration index for our analyses. Results. From the early to late 1990s, the mean maternal education level increased significantly, and the percentage of low-birthweight births declined among all groups, for both male and female births, and at all levels of the mother's education. Relative to those with less than 9 years of formal education, there was a decreasing risk of low birthweight among those with 9 to 11 years of formal education (range in adjusted odds ratio=0.69-0.82) and with 12 or more years of formal education (range in adjusted odds ratio=0.51-0.74). Between the early and late 1990s, the concentration index changed from -0.0778 to -0.0656 for male births and from -0.0717 to -0.0813 for female births. Conclusions. Education-related inequalities associated with low birthweight persisted from the early to the late 1990s in surveyed areas.