The religious calendar has been crucial in the reproductive regimes of the European population until the twentieth century and clearly defines the regime of marriages and conceptions. This paper has analysed the time of conception of all survivors in 2003 and born in Spain and has studied the number of conceptions before, during and after Lent. This period are the forty-seven days of the Christian calendar that prepare for Holy Week and range from Ash Wednesday (the day after the end of Carnival) to Easter Sunday (including Holy Week) and which in Catholicism is traditionally considered a period of sexual abstinence.

The results of our study, on the period 1940-2002, show that in the first decades of the twentieth century, conceptions have a relative peak in late spring (when Lent is over), and early summer ( and also during December), and this situation maintained during the period 1940-1979, although with tendency towards homogenization”, highlights José Manuel Pavía, researcher of the Department of Applied Economy of the University of Valencia.

“Until now, some studies have shown that religion had a clear relevance in the reproductive system prior to the demographic transition, but now we have been able to demonstrate the importance it also had in fertility until the end of the political transition”, says Carles Simó, from the Department of Sociology and Social Anthropology (UV).

A significant fact is that during the first decades of the twentieth century, the effect of Lent on the number of fertilisations increased as Easter approached, when Lent culminates, a situation that also persists during the Franco regime. This fact reinforces the theory of the importance of Catholic precepts in society, explains the work in which Josep Lledó, from the Department of Economics and Business Management of the UAH, also participates.

Other conclusions are that the greatest incidence, between 1940 and 1979, of the reduction in the number of conceptions begins to occur 18 days before Easter Sunday and that in the period 1980-2002 a significant increase in the number of fertilisations is detected during the weekends, which confirms a significant change in the patterns that explain seasonality, with respect to the period 1940-1979.

The research did not observe any significant differences between rural and urban habitat, and in both the conceptions were significantly reduced during Lent, until 1975. Researchers did detect that this fact represents a significant change with respect to the study carried out in Andalusia, in which large differences were found between large and small municipalities. As an explanation for the homogenisation in the study at the state level, they cite the rural exodus, which would have tended to the fact that many people from rural habitats had maintained their sexual behaviour in the cities.

Method

Pavía, Simó and Lledó have studied the data from the National Statistics Institute (INE), and specifically the number of births by date, size of the municipality and autonomous community. To calculate the date of conception, 280 days remain on the date of birth (9 months and 10 days). In addition, to analyse the difference between rural and urban areas, they have established six types of geographical areas depending on the size of the municipality.

Empirical analysis is done by controlling seasonality through time series methodology (regARIMA models) and comparing conceptions for equal periods of time between the beginning and end of Lent. Thus, the 47 days previous to Lent with the 47 days of this period; during Lent and the 47 days thereafter; taking the central part of the periods and after Lent; and conceptions between the 7 days previous to the end of Lent and the 7 days after with conceptions during the same length, but between the day 21 and day 7 before Lent.

Article:

Carles X. Simó-Noguera, Josep Lledó, Jose M. Pavía: “Lent impact on the seasonality of conceptions during the twentieth century in Spain". European Journal of Population. Doi: https://doi.org/10.1007/s10680-020-09555-z