ObjectiveMissed abortion occurs in ∼ 15% of all clinical pregnancies. The pathogenesis is not clearly known. However, defective placentation resulting in maternal systemic inflammatory response is considered responsible for missed abortion. Platelet lymphocyte ratio (PLR) and neutrophil lymphocyte ratio (NLR) are increasingly cited parameters of inflammation in the literature. However, no study evaluated the PLR and NLR rates in missed abortions so far. The aim of the present study is to investigate whether complete blood count (CBC) inflammatory parameters such as NLR and PLR are increased in patients with missed abortion.MethodsMedical records of 40 pregnant women whose gestation ended in missed abortion at between 6 and14 weeks of gestation and of 40 healthy pregnant women were collected and compared retrospectively. The groups were compared regarding hemoglobin, hematocrit, platelet count (PLT), mean platelet volume (MPV), platelet distribution width (PDW), PLR and NLR.ResultsPlatelet distribution width, NLR and PLR values were higher in the missed abortion group compared with the healthy pregnant women group (rates arep= 0.043;p= 0.038; andp= 0.010, respectively). Hematocrit, MPV, and lymphocyte values were found to be lower in the missed abortion group compared with the healthy pregnant women group (p= 0.027,p= 0.044 andp= 0.025, respectively).ConclusionThe PDW, NLR and PLR values of the missed abortion group were reported high; and MPV values were reported low in the present study. These findings may help to speculate a defective placentation in the pathogenesis of missed abortion.