There is clearly a Mullerian duct anomaly, with two uterine bodies being separated by a deep cleft. There appear to be two separate cervices (first image of the static series). Although no coronal imaging is available to confirm this, the appearance is of a didelphys uterus.
Within the left uterine horn, there is a normal early monochorionic diamniotic pregnancy, with beautifully demonstrated separation of the two embryos by the as yet unfused amniotic sacs.