Whoever told you that is selling something. Vitamin K is fat soluble and even the cheapest, lowest quality formulae can deliver enough of a dosage for an elephant. Unless the newborn is already bleeding, immediate supplementation is unnecessary. (Unless you're expecting to injure the newborn, in which case please get in the back of the squad car, sir, and don't bump your head.)
I suppose it's possible the newborn is already bleeding, in which case somebody should probably figure out why and address that first.
> I guess I don't see the point in rejecting the shot. It's a vitamin, it has a clear benefit, and no drawback.
Please don't give medical advice. You're not good at it.
A big whack of K (either form) in a shot can't be pulled back if it turns out to be too much for the child. If the placental diffusion just so happened to be higher for a particular child, and their levels were not so very deficient, now you've got an overdose condition to deal with.[1] Normally that's not the end of the world, but to say there's "no drawback" is just wrong. Further, it's entirely unnecessary when there are safer, titratable methods that don't involve poking a hole in the newborn, such as adding K to pumped breast milk or painting the mother's nipple. Oral dosage can be spread out over many feedings, and at the slightest indication of excess (jaundice, for example) can be discontinued without further risk.
But of course, this requires the mother to have the wherewithal to remember to do the supplementation, and modern hospital protocols are designed with the assumption that the mother is incompetent at her job. Some of us have higher opinions of women and their ability to do what women have routinely done for millennia. A cynic might also point out that the hospital can't charge you as much for a bottle of cheap gel caps as an injection.
By the way, K1 is the plant-derived form, which some of us feel is a bit better to supplement with than K2, particularly when coupled with fat intake. On the other hand, if you do intend to let the hospital shoot up your newborn instead, maybe ask to see the vial first.
[1] https://web.archive.org/web/20251206091225/https://www.vinme...