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What is Gestational sac is seen on TVS as early as : and explain in detail?
An intrauterine gestational sac is visualised with transvaginal sonography by 5 weeks of gestation, and an embryo with cardiac activity by 6 weeks. The embryo should be visible transvaginally once the mean sac diameter has reached 20mm.Cardiac motion is usually visible with transvaginal imaging when the embryo is 5mm. Reference: william's Textbook of obstetrics 24th edition page no 196.