Secular trends in anthropometrical measurements of infants in Latvia

The aim of the presented study was to find secular trends for newborns' height and weight at birth dynamics over the century in Latvia. Over the last 79 years six research papers about newborns in Riga - the capital of Latvia - have been published. The results of those different researches conducted in different periods of time were compared. The comparison of data was more difficult as the overall differentiation ratios used in other respective researches were not specified (the standard deviation, the standard error or something else). To make a comparison of the nutritional status the possible Rohrer index within each research was calculated. The research studies conducted in the first third of the last century had large research samples - a great number of new-borns was surveyed. That is the reason for small overall differentiation ratios. In the latest studies the number of the surveyed new-borns was considerably smaller, which causes the appearance of a greater standard deviation. However, no tendency to increase or decrease for the new-borns' body mass arithmetic mean was observed during the considered research studies. In addition, we found out that new-born boys in Latvia get burlier over time. The question: which dominants in causing changes in anthropometric measurements over time - the environment or hereditary - are still open.