Effects of the 2001 Extension of Paid Parental Leave Provisions on Birth Seasonality in Canada

Abstract

It is well known that there exists a strong seasonal pattern in births and that the pattern differs across geographic regions. While historically this seasonal pattern has been linked to exogenous factors, modern birth seasonality patterns can also be explained by purposive choice. If birth month of a child is at least partially chosen by the parents then, by extension, it can also be expected that this can be influenced by anything that changes the costs and benefits associated with that choice, including public policy. This paper explores the effect that the 2001 extension of paid parental leave benefits had on birth seasonality in Canada. Overall we find strong results that the pattern of birth seasonality in Canada changed after 2001, with a notable fall in spring births and an increase in late summer and early fall births. We discuss the potential effects of this unintended consequence, including those related to health and development, educational preparedness and outcomes, and econometric modelling. IntroductionIt is well known that there exists a strong seasonal pattern in births and that the pattern differs across geographic regions. 1 This display of birth seasonality has been linked to such exogenous factors as the photoperiod, climate, holidays, nutrition, urbanization, and other sociocultural and environmental factors. 2 More recently, researchers have been documenting changes in the historical seasonal patterns within countries since the advent of contraception, suggesting that modern birth seasonality patterns can also be explained by purposive choice (e.g. Van de Kaa 1987, Werschler & Halli 1992, Bobak & Gjonca 2001, Cassels 2002, Haandrikman & Van Wissen 2008. If birth month of a child is at least partially purposefully chosen by the parents then, by extension, it can also be expected that this can be influenced by anything that changes the costs and benefits associated with that choice, including public policy.There is some evidence to suggest that the timing of births can be influenced by public policy. Several studies have examined whether the delivery date of children, either delayed or expedited, is influenced by that tax treatment of children. The seminal work by Dickert-Conlin and Chandra (1999) considered the U.S. child tax benefit system that granted a whole year of tax relief to an individual or family that had a child in that tax year, even if the child was born on December 31. The authors found that such a system provided incentives for more children to be born in the last week of December rather than the first week of January; namely that a $50 increase in benefits led to a 1.4 percentage point increase in the probability of a December birth.Using a more comprehensive data source, LaLumia, Sallee, and Turner (2015), however, found a smaller magnitude: that a $1000 increase in benefits was necessary to incite the same 3 behavourial response as reported by Dickert-Conlin and Chandra (1999). Kureishi and Wakabayahsi (2008) similarly found the Japanese tax deduction for d...