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What is Earliest sign of pregnancy on TVS is? and explain in detail?
Ans. is 'a' i.e., Gestational sac "The first definitive Sonographic finding to suggest early pregnancy is visualization of gestational sac" - Callen 4th/e p. 114* The gestational sac can be visualized as early 4Vi weeks of gestation and the yolk sac at about five weeks.* The gestational sac can be visualized as early as 4Vi weeks by transvaginal USG and 5 weeks by transabdominal USG.* Fetal heart rate can be detected by TVS at 5-6 weeks.