Sex ratio at birth in Croatia: update.

There is strong evidence that the sex ratio at birth is partially determined by environmental and social factors. The modern change in those factors serves as an explanation for the secular decline in sex ratio at birth in most of the industrialized countries. This article is the reexamination of the results from my previous communication in which no trend in sex ratio at birth was established for the Croatian data from 1946 to 2007. The data for the years 2008 to 2011 were added, which didn't result with the detection of a significant change in sex ratio at birth by the regression analysis or by the Box-Jenkins time series analysis. Although the numerous factors associated with the decline in sex ratio at birth did occur during the studied period (e.g. increased exposure to the environmental pollution through food, air and water, the rise of the obesity and diabetes incidence, the economic crisis etc.), it appears that none of them made the measurable impact on sex ratio at birth. Also, the possible marginally significant decline in sex ratio at birth could be the result of a high sex ratio at birth immediately after the World War II. The results of this study caution against rapid generalization of the factors found to influence the sex ratio at birth in the epidemiological and clinical studies on the population level data.