Background: Defective placentation as a cause of many pregnancy-related conditions including abortion and ectopic pregnancy will involve abnormal inflammatory response. Assessment of different inflammatory markers as neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and lymphocyte-monocyte ratio (LMR) may aid in the differentiation of causes of bleeding in early pregnancy. Objective: To verify the ability of NLR, PLR, and LMR to differentiate cases of miscarriage or ectopic pregnancy from normal pregnancy in patients presenting with bleeding in the first trimester. Patients and Method: A prospective observational study of 150 patients presenting with bleeding in the first trimester were enrolled in the study. After history taking, clinical examination, ultrasound, quantitative beta-human chorionic gonadotropin (B-hCG), or laparoscopy, patients were allocated into three groups: miscarriage group (60 patients), ectopic pregnancy group (30 patients), and control group (60 patients) who continued their pregnancy beyond 20 weeks. For all patients NLR, PLR, and LMR were calculated. Results: NLR was significantly higher and LMR was significantly lower in ectopic pregnancy group when compared to the miscarriage group or the normal pregnancy group. A cutoff level of > 2.7 for NLR and < 3.7 for LMR has a sensitivity of 80% and 70%, and a specificity of 60 % and 80 %, respectively. Conclusion: Utilization of both NLR and LMR will aid in the differentiation of cases of ectopic pregnancy from normal pregnancy or miscarriage with an acceptable sensitivity and specificity.