RT info:eu-repo/semantics/article
T1 Decline and loss of birth seasonality in Spain: analysis of 33 421 731 births over 60 years
A1 Andres-de Llano, J. M.
A1 Ardura-Fernandez, J.
AB Background and aim: Several seasonal variations have been found in birth rates in different countries atdifferent periods. The characteristics of the rhythmic patterns vary according to geographical location andchronological changes. This study presents data on spanish birth seasonality over six decades.Methods: A time series composed of 33 421 731 births in Spain in the period 1941–2000 was analysed.The series comes from the National Institute of Statistics and was processed according to the following norms:(1) normalisation of the duration of months and years; (2) clinical analysis of temporal series (isolation of seasonal component); (3) Fourier’s spectral analysis; and (4) cosinor analysis (adjustment to the cosine curve of two harmonics).Results: Significant seasonal rhythm was found in the set of births, both for a 12-month period and a 6-month period. The rhythm shows bimodal morphology, with a pronounced birth peak in April and a smaller one in September. These peaks correspond to July and December conceptions, respectively. The major birth peak shifted to March–May between the 1940s and the 1980s. Birth rhythm changed after the 1960s, with a decrease in amplitude and later loss of seasonality in the 1990s.Conclusions: In Spain, seasonal birth rhythm shows a decline from 1970, and, finally, lack of birthseasonality in 1991–2000. This trend is similar to other European countries, although Spain shows a moreintense loss of seasonality
PB BMJ
SN 0143-005X
YR 2007
FD 2007
LK https://uvadoc.uva.es/handle/10324/64726
UL https://uvadoc.uva.es/handle/10324/64726
LA spa
NO Journal of Epidemiology and Community Health 2007;61:713–718
NO Producción Científica
DS UVaDOC
RD 14-oct-2024