How economic expectations and political polarization influence fertility rates and the number of marriages

The University of Barcelona participated in a study that uses an unexpected change of government in Spain—the Spanish Socialist Workers’ Party (PSOE) defeated the PP, against the odds, in the March 2004 general election—to examine whether changes in economic expectations affected births, abortions and marriages.

The study shows that the electoral surprise—all the polls had predicted a PP victory—had an asymmetric impact on expectations. While supporters of the winning party (PSOE) became more optimistic about the economy, confidence among supporters of the losing party (the PP) declined sharply. This abrupt change had immediate demographic consequences: In the months following the election, municipalities with the strongest support for the PP saw a decline in pregnancies, a temporary but significant rise in abortions, and a decrease in marriages.

The study, published in the Journal of Population Economics, was carried out by Llibertat González, from the Department of Economics and Business at Pompeu Fabra University and the Barcelona School of Economics (BSE); Luis Guirola, from the Institute for Research on Applied Regional and Public Economics at the UB; and Blanca Zapater, from the Barcelona Chamber of Commerce.

The study shows several notable effects of the change of government on expectations and demographics. The unexpected change of government in 2004 caused a sharp and persistent deterioration in the economic expectations of PP supporters (in the two months following the election, the expectations index fell by between 0.6 and 0.8 points). The study suggests that this decline is larger than the difference in expectations between a period of economic expansion and one of economic crisis.

In municipalities with the strongest support for the PP, researchers recorded an immediate decrease in the number of monthly pregnancies, equivalent to 0.14 fewer pregnancies per thousand women. In these same places with more PP voters, during the month following the election there was a rapid and transient rise in the rate of voluntary terminations of pregnancy of almost 0.05 per thousand women. This magnitude is comparable to the demographic effect of the introduction in 2007 of the €2,500 cheque bebé (lump-sum payment).

Consistent with the increase in abortions, the study also finds a short-term decline in marriages following a premarital pregnancy (0.048 fewer marriages per thousand women), as well as a more persistent reduction in the overall marriage rate (0.05 fewer marriages per case).

Political polarization can influence fertility rates and marriage

The study, which uses administrative data on births and abortions in Spain, not only examines the 2004 elections but also provides evidence covering the period from 2000 to 2020. The authors conducted a comprehensive analysis of all national elections during this period, using pre-election polls and survey data to determine the extent to which each result was expected or unexpected.

The findings also reveal a mechanism through which political events can affect citizens’ lives in polarized societies, such as Spain and the United States. “Polarization divides citizens along party lines and affects their preferences and beliefs. We have shown that the effects of partisanship can extend beyond the sphere of public opinion, including behaviors as important as decisions about fertility and marriage,” they conclude.

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Lisa Lock

BA art history, MA material culture. Former museum editor, paramedic, and transplant coordinator. Editing for Science X since 2021.

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Andrew Zinin

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