Extended Family Structures Exert a causal Influence on Fertility

Research of the impact of kin alloparenting on reproduction mainly focuses on mother’s parents and parents-in-law. The impact on fertility of extended families and the alloparental help with childcare they can provide has received much less attention. Moreover, there is an important lacuna in the existing studies of this problem, as it is mostly approached through correlational studies, while the presence of a causal link remains unclear. Using an instrumental variables approach, we demonstrate that prevalence of extended family structures exert a causal influence on fertility. A one standard-deviation increase in prevalence of extended families is associated with approximately 1.07 additional children per woman. These results highlight that family structure is not only statistically significant but also demographically consequential in shaping fertility outcomes.