This study aimed to assess the magnitude of singleton preterm birth and associated factors in Shire Suhul General Hospital, Northern Ethiopia. 

Institutional based cross-sectional study was conducted among 325 postnatal mothers in Shire Suhul General Hospital, Northern Ethiopia, from January to March 2018. Researchers collected the data through both face-to-face interviews and chart reviews by using pretested semistructured questionnaires. SPSS version 20 was employed to enter and analyze the data. Researchers ran both bivariate and multivariate logistic regression models to identify factors associated with singleton preterm birth at the level of P values ≤ 0.25 and <0.05 for each model, respectively. 

The magnitude of singleton preterm birth in Suhul Hospital was 16.9%. Smoking cigarette/drinking alcohol during pregnancy AOR=3.61: CI 95%; 1.59-8.23, previous abortion AOR=2.37: CI 95%; 1.15-4.88, hemoglobin level < 11gm/dl AOR=2.44: CI 95%; 1.14-5.22, visible physical neonatal congenital anomaly AOR=10.42: CI 95%; 1.66-65.23, and history of giving low birth weight baby AOR: 2.78 CI 95%; 1.39-5.55 were the factors statistically associated with singleton preterm birth. 

The magnitude of preterm birth in this study was higher than the average prevalence of preterm birth reported in Ethiopia. Supplement of daily iron with folic acid for all pregnant mothers with adequate adherence monitoring and preconception healthcare service to avoid cigarette smoking/alcohol drinking and risk detection was set as recommendations.