Fertility decline in developing countries may have unexpected demographic consequences. Although lower fertility improves nutrition, health, and human capital investments for surviving children, little is known about the relationship between fertility outcomes and female-male offspring sex-ratios. Particularly in countries with a cultural preference for sons, like India and China, fertility decline may deteriorate the already imbalanced sex-ratios. We use the fertility histories of over 90,000 Indian women in the Second National Family and Health Survey to investigate the relationship between fertility choices and offspring sex-ratios in India. Both within- and between-family-size differences in offspring sex-ratios are examined. Our analysis reveals three main findings. First, within-family-size differences show that for our reference household (i.e. non-low-caste Hindus), parental education reduces anti-female bias in survival in large families (three or more children households) but plays no role in small families (one or two children households). While a higher standard of living worsens anti-female bias in survival in both large and small families, it does so to a greater extent in small families. Small families that own land also have lower offspring sex-ratios compared to landless households. Second, between-family-size differences indicate an `intensification' effect, whereby small families have dramatically lower offspring sex-ratios than large families. The intensification effect is greatest for Sikh and non-low-caste Hindu households, followed by low-caste Hindu and Christian households, but does not exist for Muslims. Third, while maternal education and urban residence weaken the intensification effect, paternal education, a higher standard of living, and land ownership strengthen it. Our results suggest that fertility decline, together with economic growth, may worsen India's already imbalanced sex-ratios. Thus, much needed fertility control policies must be supplemented with programs that counter offspring sex-selection in favor of sons. Policies that seek to eradicate son preference by making daughters more economically attractive to parents as well as those that imbibe more gender-equal attitudes within individuals are critically needed as economic growth generates higher levels of education and wealth in India.
