One of the key strategies to reduce fertility and promote the health status of mothers and their children is adhering to
optimal birth spacing. However, women still have shorter birth intervals and studies addressing their determinants were scarce. The
objective of this study, therefore, was to assess determinants of birth interval among women who had at least two consecutive live
births. Methods. Case control study was conducted from February to April 2014. Cases were women with short birth intervals (<3
years), whereas controls were women having history of optimal birth intervals (3 to 5 years). Bivariate and multivariable analyses
were performed. Result. Having no formal education (AOR = 2.36, 95% CL: [1.23–4.52]), duration of breast feeding for less than 24
months (AOR: 66.03, 95% CI; [34.60–126]), preceding child being female (AOR: 5.73, 95% CI; [3.18–10.310]), modern contraceptive
use (AOR: 2.79, 95% CI: [1.58–4.940]), and poor wealth index (AOR: 4.89, 95% CI; [1.81–13.25]) of respondents were independent
predictors of short birth interval. Conclusion. In equalities in education, duration of breast feeding, sex of the preceding child,
contraceptive method use, and wealth index were markers of unequal distribution of inter birth intervals. Thus, to optimize birth
spacing, strategies of providing information, education and communication targeting predictor variables should be improved.