Background: Vaginal bleeding before twenty weeks of pregnancy was designated as a "threatened miscarriage" in medical terminology. Even women who experience this type of threat have a 15% higher chance of losing their pregnancy. Early pregnancy outcome prediction would be a highly advantageous for clinical approach. Aim: This study aimed to assess spiral artery flow during mid-first trimester (four–eight weeks) in instances of threatening abortion and normal pregnancies. Subjects and methods: Cohort prospective study was conducted at Obstetrics and Gynecology Emergency Unit Outpatient Clinic of Suez Canal University Hospital on forty expectant women in 1^st trimester. Participants were organized into following groups: Group A consisted of twenty pregnant women who presented with threatened miscarriage such as vaginal bleeding or spotting with or without abdominal pain, group B consisted of twenty expectant women who did not have any complaints. In all subjects, spiral artery was sonographically assessed. Results: There was a notable difference between the 2 groups concerning spiral artery pulsatility index (PI) & resistance index (RI), which were elevated in cases compared to control group, while no significant difference was observed in S/D ratio between groups. In terms of pregnancy outcomes, miscarriage rate was higher in cases (thirty percent) than in control group (zero percent). No significant differences were found between groups regarding other maternal and fetal outcome data. Conclusion: Female exhibiting vaginal bleeding demonstrated significantly elevated spiral artery pulsatility index (PI), resistance index (RI) compared to normal control group. We determined that dynamics of spiral arterial blood flow in early pregnancy (four–eight weeks gestation) can be evaluated using transvaginal color Doppler sonography.