Seasonality of birth in Korea

Abstract

Seasonal variation of average daily number of births by month in Korea was examined by a traditional time series analysis based on the data in Vital Statistics from January 1982 to December 1991. The seasonal index of births showed a bimodal pattern with a huge peak in February and another small peak in autumn (September to November) . Among associated factors to be evaluated, the seasonality of marriage was related to the seasonal variation of births. According to the analysis of coincidence, two time series showed a statistically significant coincidence in their monthly fluctuations with 10 months lag time. This result suggest that the seasonality in marriage could be one of the factors in explaining the seasonal variation of births in Korea. However, other factors including biometeorological factors, should be investigated in order to explain the seasonal characteristics of Korean birth data.