This paper studies child mortality and fertility in 61 developing countries including the Central Asian Republics (CARs). To control for simultaneity, an estimated value of fertility was used in the mortality equation and a final specification included only exogenous socio-economic, health and environmental variables. We confirm the importance of female literacy in explaining both fertility and mortality, and also find a measure of consumption for the poorest share of the population to be significant, while controlling for nutrition, health expenditure, and income distribution. Incidence of tuberculosis and female agricultural population proxy for environmental impacts, but in spite of these controls, a CARs dummy was positive and significant, indicating higher mortality rates than in other countries of similar economic development with an estimated 71% additional mortality due to living in the CARs. The results fill gaps in the literature: we use a wider range of socio-economic and environmental health variables than previously in an encompassing analysis of mortality and fertility, and find evidence of excessive mortality in the CARs most likely linked to environmental degradation in the region.