Why your newborn needs the vitamin K shot

In a hospital birth where everything goes as initially planned, there’s labor, delivery and then the post-birth care immediately provided to both the newborn baby and mom. One common aspect of that care is the vitamin K shot, given to babies within the first six hours after birth. Unfortunately, misinformation has recently found its way into influencer accounts on social media and videos online, trying to deceive worried new mothers into declining the vitamin K shot at the time it is most important to receive it.

Pediatrician Jessica Boyd, MD, explained why your newborn needs the vitamin K shot and why these deceitful statements about the shot persist online.

What is vitamin K? What makes it important?

“Vitamin K is a vitamin that helps prevent bleeding,” explained Dr. Boyd. “It comes from the foods we eat and is made by healthy bacteria in the intestines of children and adults.” 

Very little vitamin K crosses the placenta during pregnancy. Babies are born with an immature intestinal microbiome that does not yet produce significant amounts of the vitamin, and newborn diets do not provide enough. Even if a mother is supplementing her diet with vitamin K, very little can be passed on by breastmilk.

Without sufficient levels of vitamin K, babies are at risk for life-threatening bleeding into the brain and intestines for up to six months of life.

Why is vitamin K given through injection rather than orally?

“Oral doses are simply less effective than the injection, especially at preventing late-onset vitamin K deficiency bleeding, or VKDB,” said Dr. Boyd. “The oral version requires multiple doses and absorption isn’t consistent.”

For example, Denmark uses an oral regimen that must be given weekly for three months. If every single dose is given correctly and consistently without the infant spitting it up and assuming normal absorption, oral vitamin K can be helpful. Even in that ideal circumstance, it’s less effective than the form given through injection. Studies consistently show that a single injection provides the most reliable protection against VKDB, which is why the American Academy of Pediatrics continues to recommend the injection as the safest and most effective option.

“There is also no FDA-approved dosing schedule for oral vitamin K in the United States,” added Dr. Boyd. “Dietary supplements are not FDA regulated and do not need to prove they are safe or effective before being sold. Manufacturers of the oral form are also not held to the same rigorous quality standards as the injection. That might mean the strength varies, the purity of ingredients might be compromised and other problems could occur due to lack of regulation.”

Why can’t I wait to see if my baby really needs the shot instead of it being given right away? 

VKDB can happen suddenly, even in babies that seem perfectly healthy at birth. In many cases, there are no warning signs before a serious event occurs. The goal of providing it so early is to prevent bleeding before it happens. Waiting until bleeding develops would mean it will likely be too late to prevent serious complications, which might include brain injury or even death.

Because we know that all babies are born with low levels of vitamin K, the safest approach is to provide protection before bleeding happens.

Why is the vitamin K shot so important if VKDB is rare in the USA? 

“VKDB is rare in the United States because the shot is so effective,” said Dr. Boyd. “We have been giving the vitamin K shot since 1961 as standard practice. Before then, newborn bleeding from VKDB was much more common than it is today.”

Newborns who do not get a vitamin K shot are 81 times more likely to develop severe bleeding than those who do get the shot, and 1 out of 5 babies with VKDB will die. As we see more parents declining the injection, we will also see the rates of VKDB increase.  

“Sometimes the best preventive measures become so successful that we forget the diseases they were designed to prevent,” said Dr. Boyd. “I have colleagues that have been practicing for over 20 years and have never seen a case of VKDB until recently.”

I read online that the vitamin K shot has dangerous side effects for my baby.

“There is a lot of misinformation out there,” said Dr. Boyd. “Social media plays on fear because it gets attention, clicks and follows. During pregnancy, we are especially primed for the understandable nerves and fear we have over our growing families to be taken advantage of by those who don’t understand or don’t care about the truth. The vitamin K shot has been used safely for over 60 years, is effective and is supported by decades of research.”

The most common side effect is temporary soreness/redness at the injection site. Other concerns that have been raised by parents include:

• “The ingredients seem harmful.” All ingredients are FDA approved and have a long history of safety in medications. The standard shot contains preservatives but there is a preservative free version of the shot available if desired.
• “The dose is too high.” The dose stays in the muscle and is slowly released over time. This allows for protection against both early and late VKDB and no, it does not flood your newborn’s body all at once.
• “My baby doesn’t need the shot because delivery was not traumatic.” VKDB can occur suddenly in the absence of trauma and can occur within up to six months of life.
• “There is a black box warning.” This stems from a potential allergic reaction from rapid administration of the intravenous form, NOT the intramuscular form we give to babies. There have been no cases of allergic reaction to the injectable version of vitamin K given to babies in the United States, and over 240 million doses have been given since 1961.
• “I just don’t think it’s necessary.” It is true that many babies who do not receive the shot or oral doses will never experience serious bleeding. However, we cannot predict which babies will develop VKDB. Often, the first sign of VKDB is unexpected bleeding into the brain. By the time symptoms appear, a baby may already be critically ill. 

“Vitamin K is recommended not because every baby will develop VKDB, but because every baby is born with low levels of vitamin K and the consequences of bleeding can be life-threatening,” said Dr. Boyd.

“A single vitamin K injection provides safe and reliable protection during the time babies are most vulnerable. As a pediatrician, we recommend vitamin K for the same reason we recommend car seats, smoke alarms and safe sleep practices. We hope a child never needs that protection, but we want it in place before a preventable tragedy occurs.” 

What happens if I refuse the vitamin K shot?

“If you decline to give your baby the vitamin K shot, your baby will remain at risk for VKDB for the first six months of life,” said Dr. Boyd. “Because your baby will be at increased risk for life-threatening bleeding, you will also be asked to sign a refusal form acknowledging that the risks to your baby of refusing vitamin K were discussed with you.”

Surgical procedures including circumcision and frenotomy, the surgical treatment for tongue-tie, are not recommended without vitamin K protection and will be delayed until after vitamin K levels have risen.

If VKDB occurs, your child may require hospitalization, blood tests, imaging studies and other invasive procedures. A single vitamin K injection at birth can help prevent serious complications and the need for these additional interventions.

Can I ask to hold my baby while they are given the shot so I can comfort them?

Absolutely!  Skin-to-skin contact during the injection can help minimize any discomfort.  Our goal is to not only protect your baby but also to support our parents through every step of the newborn experience.

“I understand that many parents have questions about vitamin K and want to ensure that everything given to their baby is safe and necessary,” said Dr. Boyd. “As pediatricians, we also want what is best for your baby! Our goal is to provide clear and evidence-based information so that you can make an informed decision.”