Soon after birth, newborns routinely receive a vitamin K injection to help prevent a rare but potentially life-threatening bleeding disorder. While the injection has been a standard part of newborn care in the United States since the 1960s, parents often have questions about why it is needed, how it works and whether there are alternatives.
Jaspreet Loyal, MD, medical director of inpatient pediatrics at Yale New Haven Children’s Hospital and associate professor of Pediatrics at Yale School of Medicine, answers those questions.
What is vitamin K and what does it do for the body?
The body needs Vitamin K to make clotting factors that help blood clot properly. Without enough vitamin K, a newborn may not be able to stop bleeding.
Why do newborns need vitamin K?
All newborn babies are born with very low levels of vitamin K. Vitamin K is a large molecule that does not pass to the baby in breastmilk or across the placenta. Newborns have not yet developed the intestinal bacteria that help produce vitamin K. This makes them particularly vulnerable to the risk of vitamin K deficiency bleeding (VKDB), a rare but serious condition that can occur during the first weeks or months of life.
What can happen if a baby doesn't have enough vitamin K?
A baby who does not have enough vitamin K may develop VKDB, which can cause bleeding in the skin, intestines, umbilical cord area or brain.
Bleeding in the brain can occur without warning signs and may lead to brain injury, long-term disability or death. According to the Centers for Disease Control and Prevention (CDC), about half of babies who develop VKDB experience bleeding into the brain.
When is the vitamin K injection given?
The vitamin K injection is given within the first few hours after birth while the baby is still in the hospital. It is administered only once as a single injection into the thigh muscle. A single dose provides immediate protection against VKDB and protects babies for months while their vitamin K levels naturally increase.
What are the ingredients in the vitamin K injection?
The vitamin K injection contains phytonadione, a form of vitamin K1, as the active ingredient. Depending on the manufacturer, it also contains small amounts of inactive ingredients that help stabilize and preserve the medication and maintain the correct pH. Parents who want details about the exact product their baby will receive can ask their hospital or pediatrician for the package insert.
Is there an option for newborns in the U.S. to get vitamin K besides an injection?
There is no FDA-approved alternative vitamin K product for newborn prevention in the United States. Medical organizations, including the American Academy of Pediatrics, recommend the intramuscular vitamin K injection because it has been shown to be effective, especially for preventing late-onset VKDB.
Are there any long-term effects from the vitamin K injection?
Studies have not found any evidence that the vitamin K injection causes long-term health problems. The injection has been used safely in newborns since the 1960s and is recommended by major medical organizations, including the American Academy of Pediatrics and the CDC. There are no serious side effects of the injection. The known risks of vitamin K deficiency bleeding are far greater than any conceivable risk associated with the injection.
What should parents do if they are concerned or have questions?
Some parents prefer to avoid injections in newborns or have concerns about ingredients. However, extensive research has found the injection to be safe and effective. Parents should discuss any concerns with their obstetrician, pediatrician, family physician, midwife or other healthcare provider before delivery when possible. Ask about the benefits, risks, ingredients and alternatives so you can make an informed decision before your baby is born.
Reliable sources of information include the CDC, the American Academy of Pediatrics and your baby's healthcare team. These experts can help explain why vitamin K is routinely recommended and address any questions you may have.
