Pregnant in haste? The impact of foetus loss on birth spacing and the role of subjective probabilistic beliefs

Appropriate birth spacing improves the outcomes of children and mothers, but spacing intervals are short in sub-Saharan African countries. This paper investigates one of the behavioural mechanisms behind the short intervals by studying the impact of foetus loss including miscarriage and stillbirth. Since most of these pregnancy losses result from a genetic abnormality in the fertile egg, they can be considered random conditional on factors such as maternal age and fixed effects. We find that a pregnancy loss experience leads to a mechanical increase in the next birth spacing interval that includes the loss and the next conception. More importantly, we also find that a pregnancy loss brings about a decrease in the intervals for all subsequent births and that the shortening effect does not disappear throughout the mother’s life. Much of the shortening effect is explained once we introduce an individual-specific indicator for the realised probability of pregnancy loss. These results imply that pregnancy loss affects birth spacing by making mothers overestimate their probability of losing their unborn children. They further suggest a belief updating mechanism where mothers update their subjective probability of losing a pregnancy based on the results of their own pregnancies.