[3] Inclusion criteria were β-hCG and ultrasound performed on the same day and US result reporting no evidence of gestational sac, with subsequent documentation of a live IUP. Results were ...

However, the upper end of the “discriminatory zone” has continued to be used as a guideline for determining when a normal gestational sac should be visible by ultrasound. It has been generally ...

If you're less than five or six weeks pregnant, it's unlikely to find a heartbeat by ultrasound. For this reason, many providers won't see pregnant patients until they've passed this gestational age.

Background and aims: Clinical assessment of gestational age (GA) can be challenging. Several ultrasound approaches to estimate GA using cerebellar measurements have been reported, claiming to be ...

Crown-rump length is an ultrasound measurement that's used ... People with a mean gestational sac diameter (MSD) of less than 5 millimeters greater than the crown-rump length are more likely ...