Does the number of sons born affect long-term mortality of parents? A cohort study in rural Bangladesh

Abstract

It has been suggested that bearing sons increases long-term mortality in women, because sons may be more physiologically demanding to produce than daughters. In this historical cohort study in rural Bangladesh, no association between the number of sons born and mortality was seen in women in the unadjusted analyses. However, a significant reduction in mortality with the number of surviving sons was seen. In addition, after adjusting for the number of surviving sons, there was evidence of increasing mortality with the number of sons born, in women. In men, mortality also depended strongly on the number of surviving sons, but not on the number born. These data provide support for negative long-term costs of bearing sons in mothers in rural Bangladesh, and suggest that there are context-specific factors that mask the true effects of sons in some populations.

Is there an adverse effect of sons on maternal longevity?

“…Furthermore, no evidence for differential effects on longevity by the sex of offspring was found by Jasienska et al (2006) in a study of mothers in rural Poland. Similarly, Hurt et al (2006) failed to find any association between the number of sons and maternal mortality in a sample from modern-day Bangladesh. Finally, Cesarini et al (2007) reported null results for a large sample of eighteenth and nineteenth century women from northern Sweden.…”

Reply to Helleet al.

“…But our paper is a replication of Helle et al (2002), not Jasienska et al (2006), which was only mentioned in passing as part of a literature review. The claim that we misrepresented the findings in Van de Putte et al (2004) and Hurt et al (2006) is also without foundation. Van de Putte et al did not find a statistically significant association between maternal longevity and sex of offspring in their baseline specification, but only in a restricted subset, as described by Cesarini et al (2009).…”

“…Neither do Jasienska et al (2006) whose findings it is suggested that we misrepresented along with those in Van de Putte et al (2004) and Hurt et al (2006). In the words of HLJ: 'Jasienska et al (2006) demonstrated that in rural Polish population mothers with many sons were short-lived but also that daughters born had a similar association with maternal mortality.'…”

On the number of sons born and shorter lifespan in historical Sami mothers

“…. Hurt et al (2006) failed to find any association between the number of sons and maternal mortality in a sample of modern-day Bangladesh'. Likewise, the paper by Jasienska et al (2006) demonstrated that in a rural Polish population mothers with many sons were short-lived but also that daughters born had a similar association with maternal mortality.…”

“…For example, the paper by Hurt et al (2006) clearly showed that, after controlling for the effects of surviving sons, the number of sons born had a life-shortening influence on their mothers. It thus seems imprecise that Cesarini et al (2009) wrote that: ' .…”