The effects of breastfeeding and birth spacing on child survival in China.

Using data from the In-depth Fertility Survey, conducted in Shanghai Municipality and Shaanxi Province, People's Republic of China, in April 1985, this study shows that breastfeeding and birth spacing have significant effects on child survival in Shaanxi, but not in Shanghai (controlling for potential confounding factors and reverse causality). The effect of breastfeeding decreases with age. Introducing proper supplemental food is very important for child survival in Shaanxi, where a high proportion of children are breastfed exclusively for much too long, sometimes up to nine months. An increase in the length of the previous birth interval improves child survival in Shaanxi significantly, especially for high-order children, and the first child has the highest survivorship in both Shanghai and Shaanxi. The effects of subsequent birth intervals are statistically significant in Shaanxi, but have a small actual impact on child survival in the first few years of life, since the arrival of a sibling does not affect the index child's risk of dying in the first few months of life, when the mortality rate is extremely high.