Objectives: The primary outcome was to evaluate: the correlation between the ultrasound parameters assessed in the first trimester (Crown- rump length, Fetal heart rate, Uterine artery Doppler assessment and Fetal volume measurement) and silent miscarriage, the correlation between different ultrasound parameters and the correlation between the patient clinical characteristics and early pregnancy loss. Methodology: This was a prospective study that included two hundred pregnant women in the first trimester. Each pregnant women was submitted to three ultrasound scans during the first trimester where (Crown- rump length, Fetal heart rate, Uterine artery Doppler assessment and Fetal volume measurement) were assessed. Complete questionnaire was performed including: obstetric history, and symptoms of the current pregnancy. Results: In the first scan 33.3% of fetuses with a CRL below the 5th centile for gestational age miscarried compared to 8.1% of those with normal CRL (p = 0.008). (Odds Ratio: 5.7, 95% Confidence Interval: 1.7-19.2).In the second scan15.6% of fetuses with a CRL below the 5th centile for gestational age miscarried compared to 3.9% of those with normal CRL (p = 0.020). (Odds Ratio: 4.6, 95% Confidence Interval: 1.2-18.3).There was a positive correlation between CRL and fetal volume during the first scan, follow up scan and the final scan (r= 0.933, 0.900, 0.547 respectively). Two factors were associated with significantly higher frequency of miscarriage; history of previous miscarriages (p=0.008) (Odds Ratio: 5.1, 95% confidence interval 1.4-18.7) and threatened miscarriage during the current pregnancy (p = 0.003 (Odds Ratio: 5.3, 95% confidence interval 1.8-15.9). Conclusion: CRL below 5th centile for the gestational age in the first trimester was associated with increased risk of first trimester silent miscarriage. There was a positive correlation between CRL and fetal volume measurement in the first trimester. History of previous miscarriage and threatened miscarriage in the current pregnancy were associated with increased risk of silent miscarriage in the ongoing pregnancy.