What are the most common causes for unplanned C-sections?

These would be ‘labour failure to progress’ (e.g. the cervix not fully dilatating even with oxytocic augmentation); ‘obstructed birth’ (e.g. the baby’s head has become a bit malpositioned and is stuck so no longer descending even with effective pushing); and fetal distress (e.g. abnormal fetal heart rate). And all of these we can tend to see much more often with women who have pregnancy medical complications, pre-existing medical complexities, inductions, augmentations and epidurals.