WASHINGTON — The proportion of US newborns missing a routine vitamin K injection rose by more than 57% between January and June 2026, according to an analysis of more than one million births.
Health-data company Truveta examined records covering 1,026,375 infants born to 825,599 mothers between 2019 and June 2026. Non-receipt rose from 5.2% in January to 8.1% in June.
The analysis also found a sex difference. In June, 8.9% of newborn girls had not received the shot within one day of birth, compared with 7.3% of boys.
Earlier hospital research found that girls were more likely to miss the injection, possibly because hospitals may not perform circumcision on boys without vitamin K protection. That explanation remains a hypothesis rather than proof of why individual families accept or decline care.
Vitamin K helps blood clot. Babies are born with low stores because little crosses the placenta, their intestinal bacteria are not yet producing enough and breast milk contains only small quantities.
Without supplementation, bleeding can occur inside the intestines or brain without an obvious warning. The US Centers for Disease Control and Prevention says infants who do not receive the injection are 81 times more likely to develop late vitamin K deficiency bleeding.
The injection is not a vaccine and does not operate by training the immune system. Confusion has nevertheless grown as distrust of vaccines spreads into other newborn interventions.
Families deserve clear information rather than humiliation. Clinicians should explain the purpose of the injection during pregnancy, allow questions and distinguish evidence-based concerns from unsupported online claims.
Hospitals also need consistent documentation. Truveta measured whether an injection was recorded within one day of birth; that is not identical to a confirmed parental refusal in every case. A clinical delay, transfer or missing record may account for some entries.
The data do not yet establish that bleeding events increased proportionately during the first half of 2026. Researchers are examining that question.
Parents should discuss the injection with a qualified maternity or paediatric professional. A newborn with unexplained bruising, bleeding, seizures, unusual sleepiness or repeated vomiting requires urgent medical attention.
The sex disparity deserves monitoring because preventive care should not depend on whether another procedure is planned. Every infant begins life with the same biological shortage of vitamin K—and the same need for protection from a preventable bleed.
Join the discussion