Gestational sac is seen on TVS as early as :: (A) 18 days from LMP, (B) 21 days from LMP, (C) 35 days from LMP, (D) 42 days from LMP
Answer is C. 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.