Objectives: An investigation of the importance of hematological inflammatory markers on the prognosis of first trimester pregnancies and their role in predicting threatened abortion and early pregnancy loss. Material and methods: This study was carried out in the Obstetrics and Gynecology Department of the Faculty of Medicine in our University between January 2018 and May 2019. Three-hundred individuals, 100 of them diagnosed with early pregnancy loss (EPL), 100 diagnosed with threatened abortion (TA) and 100 healthy control patients (HC), participated in the study. Results: There were no statistically significant differences in terms of hemoglobin, platelet, neutrophil count and NLR between the three groups. The RBC counts were significantly lower in EPL and TA compared to HC. Similarly, it was determined that the MPV value was significantly lower in EPL compared to HC. On the other hand, there was no difference in MPV between TA and HC. The PLR was higher in EPL and TA. Conclusions: MPV, RBCs and PLR values were strongly associated with first-trimester miscarriage. These economical and easily measurable platelet indices can be used to predict fetal losses.