Received March 04, 2023
Accepted September 21, 2023

Objective: To evaluate correlation between transvaginal ultrasound detected yolk sac diameter at 6 to 12 weeks of gestation and adverse pregnancy outcome. Methods: Prospective cohort study conducted at Ain Shams University Maternity Hospital during the period (1st of July 2019 till the end of January 2020) on 120 pregnant women attending outpatient clinic at 6 to 12 weeks gestation with sure and reliable dates, transvaginal ultrasound was done to measure inner YS diameter. The range of normal diameter considered to be 2-5 mm. Cases were followed up by routine antenatal care till16th week of gestation. Results: significant association between maternal age and yolk sac diameter, YS diameter and early pregnancy spontaneous miscarriage (high percentage of positive fetal life occurred with normal yolk sac diameter (2-5 mm), (p= <0.001),yolk sac diameter<2mm positive fetal life was0.0% and negative fetal life was 42.9%, yolk sac diameter between(2-5mm) positive fetal life was81.1% and the negative fetal life was 7.1% and about the yolk sac diameter>5mm we found out that the positive fetal life was 18.9% and the negative fetal life was 50.0% with p< 0.001, x2 60.094 and the best cut off value of yolk sac sized which was >0.56, with sensitivity of 78.6% specificity of 84.3%. Conclusion: highly significant correlation between yolk sac diameter and early pregnancy loss.