Let us remind ourselves of the features of a normal early pregnancy (Fig 1).

The uterus contains a gestation sac with a bright trophoblastic halo. After about six weeks, we would expect to see an embryo within the gestation sac and the yolk sac which nourishes the early embryo.

Remember that while all these signs suggest that this is a normal pregnancy, it is critical that you also look for a heartbeat.

Fig 2 shows an early pregnancy of about 6 weeks. There is a gestation sac within the uterus and there is a very early yolk sac. This suggests that this is an ongoing pregnancy, particularly as the trophoblast appears bright. You would need to confirm the presence of a heartbeat or rescan the patient in about two weeks to confirm viability.