Gynaecology & Obstetrics Earliest ultrasound sign of pregnancy in a transabdominal ultrasound scan is : A Visible gestational sac B Apparent embryonic structures C Fundal endometrial thickening D Identifiable cardiac movements 💡 Explanation Earliest ultrasound sign of pregnancy in a transabdominal ultrasound scan is : ✓ Correct Answer: C. Fundal endometrial thickening