@Highfivemum
Face Presentation
This is another one where without your notes it's a bit difficult to answer you.
Face presentation is rare. It is usually the end result of a baby who has started off posterior (facing upwards) and then, instead of the head descending and flexing, the head deflexes.
A face presentation in itself isn't a reason for a CS. There would have to be concomitant fetal distress and/or doubt over your pelvic measurements.
Yes, of course it's possible to know that a baby is presenting by the face prior to full dilatation - unless it hadn't got as far as being a face presentation when you were examined earlier in your labour. What I mean is this - in earlier labour the baby might not have been a face presentation. It might have taken the whole labour for your baby's head to have deflexed enough to be presenting by the face by the time you were fully dilated.
There is also a much rarer phenomenon, in which the face itself is posterior.
So without your notes it's really difficult to work out what was happening and how it happened.
Was your first baby delivered vaginally or was this second baby a VBAC?
Babies presenting by the face are not usually more stressed than babies presenting by the vertex (crown of the head) but if there was fetal distress that could be why you were delivered by CS.
I have delivered face presentations vaginally without incident - also breeches (and twins.)