Effect of birth order on the role of covariates of reproductive responses to childhood mortality in Bangladesh

Limited research has been conducted on the relationship between childhood mortality and subsequent fertility in developing countries. A recent study conducted in Bangladesh found a significant relationship between childhood mortality and fertility. This paper extends that analysis to investigate the role of birth order in the relationship between childhood mortality and fertility. We hypothesize that fertility regulation interacts with childhood replacement behavior in that low order children who die would be more likely to elicit replacement behavior than deaths following the survival of multiple children. We test this hypothesis with prospective longitudinal data on births and childhood deaths occurring to nearly 8,000 mothers observed in Bangladesh over the 1982-1993 periods. Parametric hazard-regression analyses are employed to assess the role of birth order in the relationship between infant-child mortality on the hazard of conception. Results show that childhood mortality increases the hazard of birth-interval closure if the death occurs in the index interval, representing the combined effect of biological and volitional replacement. Substantial birth-interval effects are also evident if the death occurs during a prior birth interval, signifying a volitional replacement effect alone. Moreover, mortality effects in prior birth intervals are consistent with the hypothesis of insurance effects. Interaction of replacement with elapsed time suggests that the volitional impact of child mortality increases as the demographic transition progresses. However, these relationships are not altered when statistical controls are introduced for birth order, indicating that the volitional effects of childhood mortality are independent of the number of children surviving.