LAUSR

Objective This study aimed to determine whether the birth interval changes differently over time among women in Ethiopia and whether the change depends on women, children and household characteristics measured at the last visit. Methods Longitudinal study design was implemented based on the data obtained from the 2019 Ethiopia Mini Demographic and Health Survey consisting of a total of 3630 mothers. Generalised estimating equation and generalised linear mixed model were employed to estimate the effect of the determinants given the correlation between birth intervals within a mother is under consideration. Results The majority of women were Muslims (48.1%) and come from rural areas (82.2%). About 77.2% of women at first birth were below 20 years old. A significant correlation (p value <0.0001) between the first and second birth intervals of mothers was observed. The estimated birth interval of women from the poorest household was 0.877 (e−0.1317) times the estimated birth intervals of women from the richest household. This indicates richest households were likely to have higher birth intervals as compared with the poorest households (95% CI e−0.1754=0.839 to e−0.088=0.916). Conclusion The birth intervals of over one-fifth of mothers were 1 year, less than the birth interval recommended by the WHO standard. It was also perceived that successive birth intervals are correlated. Mothers who have delivered female children had lower birth intervals than mothers who have delivered male children. As compared with the birth intervals of mothers from a household with higher economic status, the birth intervals of mothers from a household with lower economic status had lower birth intervals. In this study, significant effects of religion, contraceptive use, region, mothers’ current age, education level and mothers’ current marital status on birth intervals were also noted.