Is It Safe to Give My Newborn the Vitamin K Shot?

If you’re pregnant – or planning to be soon – you may have come across online rumors claiming the vitamin K shot is unsafe for newborns. But the evidence-backed reality is, the vitamin K shot is crucial for keeping your baby healthy from the moment they’re born. 

“It's very important to give the vitamin K shot within the first six hours of a baby’s life to prevent rare but life-threatening intracranial bleeding,” says Aqsa Inkisar, MD, a pediatrician at Hackensack Meridian Children’s Health, who is leading a team of residents focused on educating parents and staff about the importance of vitamin K. 

Learn more about why newborns need the vitamin K shot, including why the nutrient can’t be given orally.

Why Does My Baby Need the Vitamin K Shot at Birth?

Vitamin K is essential for blood clotting. It helps the body make clotting factors – proteins in the liver that act like “brakes” to stop bleeding when a blood vessel is injured. Without enough vitamin K, even a tiny bleed can result in dangerous internal bleeding.

Babies are born with very low levels of vitamin K, says Dr. Inkisar. Unlike other nutrients, vitamin K doesn’t cross the placenta well, and breast milk contains very low levels of it. That’s why it’s crucial for newborns to be supplemented with vitamin K when they are born. 

If a newborn doesn’t receive vitamin K, they could develop a rare but life-threatening condition called vitamin K deficiency bleeding (VKDB), which causes excessive bleeding that cannot be stopped. The bleeding can occur anywhere but commonly happens in the intestines and brain, potentially causing brain damage and even death, according to the Centers for Disease Control and Prevention (CDC). 

VKDB is especially scary because it can happen after you’ve left the hospital. “It can occur after a few weeks or up to six months after birth,” explains Dr. Inkisar. According to the CDC, babies who do not receive the vitamin K shot at birth are 81 times more likely to develop late VKDB than those who do. 

Is the Vitamin K Shot Safe for My Infant? What Are the Side Effects?

The vitamin K shot has been safely administered to infants in the U.S. since 1961. “It’s one of the most well tolerated interventions that we do for newborn babies,” says Rose Martine St. Fleur, MD, a pediatrician at Hackensack Meridian Children’s Health. 

Side effects are rare, but when they do occur, they may include swelling, irritation, or redness at the injection site. Nurses monitor your baby after the injection, and mothers are encouraged to soothe them with skin-to-skin contact or breastfeeding. 

Is the Vitamin K Shot a Vaccine?

Despite what may be circulating on social media, the vitamin K shot is not a vaccine. “Because it’s an intramuscular injection that’s given the way that a vaccine is given, some people think it’s a vaccine,” notes Dr. Fleur. But it’s actually just a concentrated dose of vitamin K. 

Can Vitamin K Be Given to My Baby Orally?

It’s understandable to want to avoid giving your baby a shot. Unfortunately, administering vitamin K orally isn’t as effective as giving it as a shot. 

“Oral vitamin K isn’t able to prevent the most serious and life-threatening forms of vitamin K deficiency, specifically the bleeding that occurs in the brain,” explains Dr. Fleur. “That kind of bleeding is how babies die from VKDB.” Because of this, many hospitals—including HMH—don’t even offer vitamin K orally.

Why Is Vitamin K Important for Male Babies in Particular? 

If you’re planning on circumcising your baby boy, the vitamin K shot is a must since any surgical procedure raises the risk of uncontrolled bleeding. For that reason, “newborn baby boys cannot be circumcised without getting the vitamin K injection,” notes Dr. Inkisar.

The Bottom Line

The vitamin K shot is a low-risk, high-reward intervention. “It’s a very safe and effective way to prevent a disease that can be fatal in your baby,” says Dr. Fleur. “We strongly recommend it for the ultimate safety of your child.”

Next Steps & Resources:

• Meet our sources: Aqsa Inkisar, MD and Rose Martine St. Fleur, MD
• Make an appointment online with an OBGYN near you, or call 800-822-8905. 
• Learn more about maternity and pediatrics at Hackensack Meridian Health.