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Images by Genevieve Carbonatto
A 9 week pregnant lady presents to the Emergency department with PV spotting. Her scan shows a retroverted uterus and twin pregnancies within one gesttaional sac. These are monozygotic twins. It is difficult to identify each twin seprately but there are definately 2 heart beats visible which can both berecorded using M mode.
2 heart beats are visible within the single gestational sac
Both fetal heart beats recorded using M mode