(The Hill) — More American newborns are not being given vitamin K shots, according to a study published Monday in the Journal of the American Medical Association.

The study found that from January 2017 to December 2024, 3.92% of the more than 5 million newborns in a U.S.-based electronic database did not receive a vitamin K shot. The share of newborns who did not receive the shot rose from 2.92% in 2017 to 5.18% in 2024.

Babies are born with low levels of vitamin K, which is used by the body to form clots and stop bleeding, according to the Centers for Disease Control and Prevention. Potentially life-threatening bleeding may result from low levels of the vitamin.

The American Academy of Pediatrics has, since 1961, recommended that newborns receive a single shot of vitamin K at birth. The CDC notes that newborns who do not receive the shot are 81 times more likely to develop severe bleeding than those who do.

The study also found that a newborn’s race and ethnicity were associated with whether they received a vitamin K shot. Roughly 4.3% of non-Hispanic White newborns did not receive a vitamin K shot during the eight-year period, the highest of any known racial or ethnic group.

The authors noted that the changes in vitamin K administration rates “may not have resulted solely” from skepticism of public health measures during the COVID-19 pandemic, as the increase in infants who did not receive a vitamin K shot began before 2020.

The data consists of records from 403 hospitals, all of which reported at least 10 births per year from 2017-24, across all 50 states and Washington, D.C