We don't do vit K. We haven't for either kids and wont for this baby.
Basically its given to help clotting. So the reason its given as a preventive shot is in case the child has an unknown brain bleed. Truely the oral doesnt work the same way and can't. You give it slowly over time so it wouldn't be enough to prevent a brain bleed if it takes how ever many weeks to give the full dose of the shot. By then the effects of a brain bleed not reversible.
We always write on our birth plan no vit K unless the birth is tramatic. Then we will discuss it with our midwife. They always think this is a good way to go. If the birth was very tramatic (forceps, vacuum, very fast/beyond normal pushing or whatever). We would then consider it and discuss the need.
I'm mobile.... sorry for the typos!