This is a topic most parents don't even know they should be making a decision about. Instead it simply happens as part of the routine procedures birthing moms and their newborns are subjected to within a hospital setting. Over the years some of my clients have opted out of doing Vitamin K in any form. When I first became involved in the birth community the home birth midwives were not giving Vitamin K at all. Now most of these same midwives have begun giving oral Vitamin K. Conversely to ask that your newborn not receive Vitamin K injection within the first moments of life created quite a stir in our local hospitals when I started going to births. It had to be OK'd by the pediatrician with the parents signing an "against medical advice form." These days our local nurses feel comfortable with delaying the injection for close to 2 hours and will not try too hard to dissuade you if you are refusing it out right. You need to talk this over thoroughly with your midwife or OB and pediatrician ahead of time. Licensed Midwife, Edana Hall told me some local pediatricians will not do a circumcision unless the newborn has recieved injectible rather than oral vitamin K. If you are planning to circumcise your son before you leave the hospital it is recommended he receive a vitamin K injection. If you are thinking about refusing the Vitamin K all together, I would encourage you to wait until after the birth to make a final decision. Some of the risk factors can occur during the birth process and should weigh into your final decision.
You need to do more research. Here is a link to an informative article a past client sent me about this topic. Dr. Mercola explains the reason to give Vitamin K to your newborn. He includes a list of risk factors which would make it more important for your individual baby. He also explains why it should not be done by injection. He discusses the science proving the effectiveness of oral Vitamin K and how it should be given. There is also some explanation of using supplementation of the breastfeeding mother's diet with oral Vitamin K as a delivery method for the baby.