Two U.S. lawmakers called on the CDC to track and address rising refusals of vitamin K shots for newborns, citing ProPublica reporting on cases where unvaccinated infants developed severe bleeding — including brain and abdominal hemorrhages — requiring hospitalization. Vitamin K prophylaxis is a standard preventive treatment that prevents hemorrhagic disease of the newborn, a condition that is rare but potentially fatal without the shot. ProPublica's investigation appears to have prompted congressional attention to what medical professionals describe as preventable harm tied to vaccine hesitancy spreading to routine newborn care.