Note: Here is a link to extensive article on Evidence-Based Medicine on why its so important to be sure every baby received Vit K. However, it does not deal with the issue of the oral route vs. injectable. However, that is another issue — late-onset of HDN, which occurs after 12 wks. According to current research, prevention of late-onset of HDN requires the injectable dose.
http://evidencebasedbirth.com/evidence-for-the-vitamin-k-shot-in-newborns/
This is Cochrane Database info.
Interestingly, it hasn’t been updated in 14 years, and I suspect it’s because nothing much has been studied since that time (which is why the CPS guideline is also not recent):
Two eligible randomized trials, each comparing a single dose of intramuscular vitamin K with placebo or nothing, assessed effect on clinical bleeding. One dose of vitamin K reduced clinical bleeding at 1-7 days, including bleeding after circumcision, and improved biochemical indices of coagulation status. Eleven additional eligible randomized trials compared either a single oral dose of vitamin K with placebo or nothing, a single oral with a single intramuscular dose of vitamin K, or three oral doses with a single intramuscular dose.
None of these trials assessed clinical bleeding.
Oral vitamin K improved biochemical indices of coagulation status at 1-7 days. There was no evidence of a difference between the oral and intramuscular route in effects on biochemical indices of coagulation status.
A single oral compared with a single intramuscular dose resulted in lower plasma vitamin K levels at two weeks and one month, whereas a 3-dose oral schedule resulted in higher plasma vitamin K levels at two weeks and at two months than did a single intramuscular dose.
And:
A single dose (1.0 mg) of intramuscular vitamin K after birth is effective in the prevention of classic HDN. Either intramuscular or oral (1.0 mg) vitamin K prophylaxis improves biochemical indices of coagulation status at 1-7 days. Neither intramuscular nor oral vitamin K has been tested in randomized trials with respect to effect on late HDN. Oral vitamin K, either single or multiple dose, has not been tested in randomized trials for its effect on either classic or late HDN.
Bear in mind that Cochrane is RCT’s only. The rarer outcomes of vitamin K deficiency, both classic and late, would be difficult to assess through RCT, because the numbers are so low.
