What's already known about this topic?
- Cases of early pregnancy diagnosis of body stalk anomaly are relatively few, particularly in twins.
What does this study add?
- This is the first diagnosis of concordant body stalk anomaly in monoamniotic twins before 10 gestational weeks.
- The observation of an intact amniotic cavity with both embryos showing the same anomaly supports a primary ectodermal failure as the cause for body stalk anomaly.