Objectives: the aim of this retrospective study was to assess if a first trimester subchorionic hematoma (SCH) influences the pregnancy outcome and whether pv bleeding can be a prognostic factor for the pregnancy course. Material and methods: the study included 185 pregnant women hospitalized due to symptoms of a threatening miscarriage. Patients were divided into 2 groups: 119 women with SCH (study group) and 66 patients with normal prenatal scan (control group), further subdivided into cases with and without pv bleeding, irrespectively of the outcome of the ultrasound scan. Obstetric and neonatal data were analyzed. Results: 1. A pregnancy complicated by SCH is more often associated with a poor outcome – 23.78% of the study group patients had a miscarriage vs. 1.62% of the controls. 2. Pregnancy with SCH is more likely to be lost before 9 weeks of gestation. 3. The ‘N” ratio, that expresses the maximal length of the hematoma to the maximal length of the fetus, equal to 2.5 or more, is associated with a risk of miscarriage. 4. The surface area of SCH equal to 280mm2 or more is more likely to reveal with vaginal bleeding. 5. Vaginal bleeding can be a prognostic factor for the mode of delivery – a higher rate of the Cesarean section is observed in patients with pv bleeding. 6. SCH is a complication that occurs in older women, with the limit of 30 years of age. 7. In this study there were no significant correlations between subchorionic hematoma or pv bleeding and PTL, IUGR, PIH, abnormal volume of the amniotic fluid, parity and order of gestation and delivery. Conclusions: subchorionic hematoma can be associated with poor pregnancy outcome and the ”N” index may be a useful predictor of the further course of a pregnancy. Pv bleeding may be a prognostic factor for the delivery mode.