Effect of Birth Interval on Foetal and Postnatal Child Growth

Although available evidence suggests short birth intervals are associated with adverse perinatal outcomes, little is known about the extent to which birth spacing affects postnatal child growth. The present study assessed the independent association of birth interval with birth weight and subsequent postnatal growth indices.

This retrospective cohort study carried out in the rural areas of Kassena-Nankana district of Ghana compared postnatal growth across different categories of birth intervals. Birth intervals were calculated as month difference between consecutive births of a woman. The study population comprised 530 postpartum women who had delivered a live baby in the past 24 months prior to the study.

Using the analysis of covariance (ANCOVA) that adjusted for age of the child, gender of the child, weight-for-length z-score (WLZ), birth weight, adequacy of antenatal care (ANC) attendance, and dietary diversity of the child, the mean length-for-age z-score (LAZ) among children of short preceding birth interval (<24 months) was significantly higher than among children of long birth interval (that is, at least 24 months) ((0.51 versus -0.04) (95% CI: 0.24-0.87), p = 0.001). The adjusted mean birth weight of children born to mothers of longer birth interval was 74.0 g more than children born to mothers of shorter birth interval (CI: 5.89-142.0, p< 0.03).

The results suggest that a short birth interval is associated positively with an increased risk of low birth weight (an indicator of foetal growth), but birth spacing is associated negatively with the LAZ (an indicator of postnatal growth).