Vitamin K Controversy
This article and others on both sides of the argument are found on gentlebirth.org.
http://www.gentlebirth.org/archives/vitktop.html
According to Dr. Cees Vermeer, PhD, Associate Professor of Biochemistry at the University of Maastricht (in The Netherlands), the world’s leading specialist in vitamin K, "Vitamin K shots are completely unnecessary for your newborn."
The forces of nature are so focused on a successful birth that it just seems unlikely that all babies are deficient in vitamin K. Instead of simply accepting that nature goofed about clotting factors in newborns, I thought about all the ways that interventions at birth interfere with the normal physiological birth process regarding clotting. The most obvious intervention is premature cutting of the umbilical cord; this deprives a newborn of 25% to 40% of the physiological blood volume, and thus 25% to 40% of the physiological clotting factors that nature intended to be present in the newborn's blood. As someone who does Newborn Screening heelsticks on newborns whose umbilical cords were not cut prematurely (and some of whom did not receive supplemental vitamin K), I can tell you that they have no trouble clotting normally. This solves the problem of early-onset or classical HDN.
Although vitamin K doesn't pass easily from the mother's bloodstream to the newborn through the placenta, it DOES pass easily through breastmilk. (Doesn't this seem like a strong clue that nature is actually protecting the baby somehow by managing the clotting factors in a very specific way?) Women who eat lots of fresh, leafy green vegetables will pass the vitamin K through to their babies, and this will protect them from late-onset HDN.
So, maybe nature got it right, after all, and all we have to do is support physiological health by waiting at least 5 minutes after the birth to cut the cord and by encouraging nursing mothers to eat lots of fresh, leafy green vegetables (or take a vitamin K supplement).
Some exceptions are:
Some maternal medications interfere with vitamin K, such as anticonvulsants, anticoagulants, and antibiotics. [Maternal vitamin K supplementation that is administered prenatally may prevent this form of HDN.
Vitamin K generation is also inhibited in babies who have received antibiotics.
A very few babies will have a liver disorder that prevents the normal production of vitamin K in the newborn's gut; symptoms tend to appear slowly.
Other risk factors include diarrhea, hepatitis, cystic fibrosis (CF), celiac disease, and alpha1-antitrypin deficiency.