Presentation
Confirmed pregnancy of 7 weeks. Ultrasound done to establish gestational age.
Patient Data
Ultrasound finding of an irregular 23.9 mm gestational sac without a fetal pole.
Case Discussion
At the time of initial publication, this case was considered diagnostic of an anembryonic pregnancy ("blighted ovum"). However, since then more stringent criteria have been applied to the diagnosis of failed early pregnancy.
According to current diagnostic guidelines, an anembryonic pregnancy may be diagnosed when there is no fetal pole identified, and MSD≥25 mm on transvaginal scanning.
In this case, MSD is just below this cutoff. Therefore, although it almost certainly represents a failed early pregnancy, this diagnosis cannot be made formally. Since neither fetal viability nor pregnancy failure can be confirmed, the case forms under the umbrella of "Pregnancy of uncertain viability (PUV)".