BackgroundIncomplete abortion can be managed medically or surgically at a health facility by trained healthcare providers. However, women develop unfavorable management outcomes of incomplete abortion following initial management. ObjectiveThis study aimed to assess the management outcome of incomplete abortion and its associated factors at Injibara General Hospital, Northwest Ethiopia. MethodsA health facility-based retrospective cross-sectional design was conducted from May 1/2018 to April 30/2020. A medical record review of 260 women who received abortion service was done and 236 cases managed for incomplete abortion were included in the study with a response rate of 90.8 %. Logistic regression analyses were employed to estimate the crude and adjusted odds ratio with a confidence interval of 95 % and a P-value of less than 0.05 considered statistically significant. ResultsThe findings of this study showed that 12.3 % of the women developed unfavorable management outcomes of incomplete abortion. Women who are found in the age group of 15–25 years, gestational age >13 weeks, seek care after 24 hours of the onset of symptoms, and medical management of the incomplete abortion were associated with unfavorable management outcomes of incomplete abortion. ConclusionConsidering its effect on maternal health, this study showed that the unfavorable management outcome of incomplete abortion was higher. Women's age, gestational age, the timing of seeking care, and method of management were associated with unfavorable management outcomes of incomplete abortion. Therefore, it is necessary to counsel women on the danger signs of early pregnancy and the advantages of early care-seeking.