The first hours after delivery are busy ones for your baby, involving a host of newborn screenings to make sure he’s healthy and thriving. One of the standard procedures you can expect is a vitamin K shot — a safe and effective method to prevent a very serious bleeding condition that can occur in young children.
Read on for more about your newborn’s vitamin K shot, including why it’s important and what you can expect during and after your baby gets it.
What is vitamin K and what does it do?
Vitamin K is a fat-soluble vitamin the body uses to clot the blood and stop bleeding. Unlike other fat-soluble vitamins, very little vitamin K is carried in the blood. Most is quickly metabolized by the body and excreted.
We get most of our vitamin K from green leafy vegetables, although some animal-based foods (such as chicken and ham) contain it in much smaller amounts. The good bacteria in our guts also produce a little vitamin K.
Why is vitamin K given to newborns?
Giving your baby a vitamin K injection soon after birth greatly reduces the chances of vitamin K deficiency bleeding (VKDB), a potentially life-threatening condition.
"All babies are at risk for vitamin K deficiency bleeding at birth because they aren't born with enough vitamin K, which is needed for blood to clot normally," says Micah Resnick, M.D., a pediatrician with TriHealth in Cincinatti, Ohio, and a member of the What to Expect Medical Review Board. "If they do not receive the vitamin K shot within six hours of birth, there is a chance a baby's blood can't make clots, and [they] can't stop bleeding."
VKDB — also known as hemorrhagic disease of the newborn — is most common in the first days of life, but it can appear up to six months after birth.
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All babies have very low levels of K when they’re born (known as vitamin K deficiency), because very little makes it across the placenta during pregnancy. Newborns also don’t have the good, vitamin K-producing bacteria in their intestines yet, and they don’t get enough vitamin K from breast milk alone.
That means that a small percentage of otherwise healthy infants — nearly all of whom haven’t received a vitamin K shot — experience VKDB.
"Babies are not born with [enough] vitamin K, which helps your blood clot, so I think that it's very important," says What to Expect Community parent maebee1234.
Newborns who have VKDB may bleed anywhere in their bodies, including the brain, stomach, and intestines, and their bodies aren’t able to clot the blood to make the bleeding stop. Although babies with VKDB may have no noticeable symptoms, some have blood in their stool or urine, or they may ooze blood around the umbilical cord stump or nose, or have bruising on the head or face.
Babies with VKDB may require blood transfusions or surgery, and bleeding in the brain can lead to permanent brain damage or worse.
Getting a vitamin K shot in the hours after birth is the best way to prevent VKDB in babies. In fact, babies who don’t receive a vitamin K shot are 81 times more likely to have VKDB than those who do, according to the Centers for Disease Control and Prevention (CDC).
"In recent years, more parents have refused the vitamin K shots for their newborn infants," Dr. Resnick says. "This has led to an increase in the numbers of babies with late-onset vitamin K deficiency bleeding (VKDB)."
When should vitamin K be given to newborns?
All newborns receive a vitamin K shot within the first six hours of birth. And you won’t have to ask for it: Getting the vitamin K shot is a standard practice that the American Academy of Pediatrics (AAP) first started recommending for all newborns in 1961.
Don’t wait to see if your baby needs a vitamin K injection. All infants — even those who are otherwise the picture of health — can develop VKDB, and are considered at higher risk for the condition until they start eating solid foods around 6 months.
Because bleeding occurs internally, often in the brain or intestines, you may not know it’s happening until severe complications have occurred.
"Vitamin K shots proved to be a medical breakthrough against a dangerous disease reported as far back as the 1800s," says Dr. Resnick.
How much vitamin K is given to newborns?
About 0.5 to 1 milligram of vitamin K is administered in one of your baby’s thighs. This amount is safe for babies: Most is stored in the liver, and the rest is gradually released over the next two to three months.
By then, your little one will soon start getting enough vitamin K from his diet and his body will be producing it better on its own.
Do vitamin K shots have any side effects?
Side effects from the vitamin K shot are similar to other injections and may include pain, burning, bruising, or swelling at the injection site.
Know that the vitamin K shot and all of its ingredients are safe. It does contain the (very common) preservative benzyl alcohol in an amount so low that it poses no issues for even the smallest babies.
The AAP has found no association between the shot and childhood leukemia or other cancers, adding that there’s no theoretical reason the shots would be associated with cancer.
Oral vitamin K vs vitamin K shots
While most countries give vitamin K shots to all newborns, a few places offer babies daily oral doses of vitamin K instead of the one-time shot. However, research has shown that oral supplements are significantly more likely to fail and result in VKDB than the vitamin K shot.
Keep in mind that you can’t increase vitamin K levels in your breast milk by eating certain foods or even taking a supplement. A vitamin K shot is the most effective way to prevent VKDB.
Rest assured that the vitamin K shot is safe. If you’re anxious about giving your baby a shot at such a young age, ask your doctor if you can breastfeed or hold your baby while it’s being administered, which research shows can help soothe newborns.
Vitamin K is "extremely important and safe for baby to get," says What to Expect Community user ElevatorMusic.
The bottom line? The vitamin K shot given to newborns shortly after birth is the best way to protect your baby from a serious but preventable condition.
Your newborn will undergo a number of screenings in the hours after he’s born. One procedure you can expect during this time is a vitamin K shot, which greatly reduces the chances that your baby will develop something called vitamin K deficiency bleeding (VKDB).
VKDB can affect young babies. That’s because all infants have low levels of vitamin K at birth, and don’t produce enough in their intestines or get the vitamin from solid foods until they’re around 6 months old. During this time, all babies are at higher risk of VKDB.
This condition is very serious. Newborns with VKDB may bleed anywhere in their bodies, including the brain, stomach, and intestines, and aren’t able to clot the blood to make the bleeding stop. Little ones with VKDB may require blood transfusions or surgery, and bleeding in the brain can lead to permanent brain damage or worse. Often, there are no noticeable symptoms.
Rest assured that the vitamin K shot your baby receives is very safe. Side effects from the shot are usually mild, and may include pain, burning, bruising, or swelling at the injection site. And this quick shot is the surest way to protect your little one from a serious but preventable condition.
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