Fertility History and Post-Reproductive Longevity in a Long-Living Population: Villagrande (1830-2013)

Michel Poulain, Tallinn University and Université Catholique de Louvain
Dany Chambre, Independent Researcher
Gianni Pes, Università degli Studi di Sassari

We have analyzed the relationship between the fertility of mothers who survived age 50 (n=522) and their overall lifespan. We found that, adjusting for potential confounders (year of mothers’ birth, survival of spouse), delayed childbirth is associated with a reduced mortality risk (HR: 0.969), in particular, a 3-year delay in the average age at delivery is associated with a 10% reduction in mortality. These findings support the hypothesis that a delay in childbearing is favorable to a mother's survival. We also found that a higher proportion of male children decreases the mortality risk of the mother and that the survival of mothers whose average age at the birth of sons is > 35 is consistently better (p=0.005; log-rank test). Such results are in disagreement with other recent findings and we suggest further investigations of the impact of the socio-cultural characteristics.