Vitamin K deficiency bleeding is uncommon with a birth shot; without it, late VKDB occurs in about 4–7 per 100,000 newborns.
Parents hear the question a lot: how common is vitamin K deficiency in newborns? The short answer is that bleeding from low vitamin K, called vitamin K deficiency bleeding (VKDB), is rare when babies get the shot at birth. When the shot is refused or delayed, the risk rises, and late VKDB can be severe.
Vitamin K helps a baby’s blood clot. Newborns start life with low stores, breast milk has very little, and gut bacteria that make vitamin K are not set up yet. That is why hospitals give a one-time dose soon after delivery. The CDC reports that late VKDB drops to fewer than 1 in 100,000 births when the shot is given.
Vkdb types and baseline likelihood
VKDB comes in three windows. Early (first 24 hours), classic (day 2–7), and late (2 weeks to 6 months). The table below shows the time frame, typical clues, and how often it appears when no prophylaxis is used.
| Type | Usual timing & clues | Estimated rate without prophylaxis |
|---|---|---|
| Early VKDB | Within 24 hours; bruising, oozing, internal bleeds; often linked to maternal meds that block vitamin K | roughly 6–12 per 100 births in at-risk infants; lower in the general population |
| Classic VKDB | Day 2–7; bleeding from cord stump, nose, gut, or a procedure site | around 0.25%–1.7% of births |
| Late VKDB | 2 weeks–6 months; often presents as brain bleed; usually in breastfed infants | about 4.4–7.2 per 100,000 births |
These baseline numbers come from national surveillance and reviews from multiple regions. They also explain why a single dose given in the delivery room has become standard care in many countries.
Vitamin k deficiency in newborns: how common is it now?
With routine intramuscular (IM) vitamin K at birth, late VKDB can fall to under 1 per 100,000. A Swiss report found 0.87 per 100,000. An oral program in the Netherlands saw about 3.2 per 100,000. The American Academy of Pediatrics backs IM dosing for all infants.
So in day-to-day terms: in places where nearly every baby receives IM vitamin K, late VKDB is now very rare. When oral programs are used, rates vary by dosing schedule and adherence. Where parents often decline any prophylaxis, case clusters still appear.
What raises risk for VKDB?
Most babies who bleed late share one or more of these features:
- No vitamin K at birth, or missed doses in an oral plan
- Cholestasis or other fat-malabsorption disorders
- Exclusive breastfeeding, especially with poor intake
- Preterm birth or illness that limits feeding
- Antibiotics that disrupt gut flora
Breast milk holds 1–9 mcg/L of vitamin K, while standard formula is enriched. That gap is one reason late VKDB is seen mainly in breastfed infants who did not get IM vitamin K at delivery. Clinical guides, such as those from Stanford Newborn Nursery, outline these patterns in detail.
Shot versus oral drops: what parents should know
IM vitamin K at birth covers early, classic, and late windows with one dose. Oral regimens demand repeat dosing and strict adherence, and protection against late VKDB can be patchy. Late bleeds often strike in month two or three, long after the first clinic visit, so missed oral doses matter.
The table below summarizes real-world protection:
| Method | Protection against VKDB | Notes |
|---|---|---|
| IM vitamin K, single dose at birth | Near complete for early and classic; late VKDB often <1 per 100,000 | One dose; durable tissue stores; widely used |
| Oral vitamin K, multi-dose schedules | Good for early and classic; late rates reported 1–6 per 100,000 or higher | Needs multiple doses; gaps raise risk; regimens vary by country |
| No prophylaxis | Early/classic up to 0.25%–1.7%; late 4.4–7.2 per 100,000 | Highest risk; clusters still reported when uptake drops |
How refusal affects the numbers
When refusal rises, late VKDB reappears. Case reports from the United States have traced clusters to regions with higher rates of refusal, often linked to online myths about ingredients or side effects. In one multi-year review, most late cases without prophylaxis were tied to parental refusal.
Programs that pair clear counseling with easy access to IM dosing keep uptake high and VKDB low.
What the birth dose looks like
IM vitamin K is given in the thigh during the first hours after delivery. The usual dose is 0.5–1 mg, adjusted for weight and local policy. The injection can be given before the first feed. The AAP and many public health groups recommend this timing for all newborns unless there is a medical reason to delay.
If parents ask about oral alternatives, teams should review the exact schedule and what follow-up is needed. In places with mixed IM and oral practices, clinics often track doses in the child’s record and give reminders for each scheduled oral dose.
Symptoms parents should not ignore
VKDB can be silent until bleeding starts. Call your care team urgently if you see any of the following:
- Bleeding from the nose, mouth, umbilical stump, or a heel stick
- Bruising, especially around the head or face
- Black or bloody stools, or blood in vomit
- Pale skin, poor feeding, or extreme sleepiness
- Seizure, a bulging soft spot, or repeated vomiting
The CDC fact sheet lists more warning signs and stresses that many babies show no early clues before a serious bleed. Fast care saves lives.
Why rates differ by country and program
Countries choose between IM and oral programs for many reasons. Some weigh cost and supply. Others aim to support care outside hospitals. Differences in dosing plans and how well families can follow them help explain the spread of late VKDB rates in the literature. In general, programs anchored on IM dosing report the lowest late VKDB rates.
Breastfeeding, feeding patterns, and VKDB
Breastfeeding has many known benefits. It also contains low vitamin K, so the birth dose is still needed. Babies who are mixed-fed or formula-fed have higher intake of vitamin K after discharge, but the birth shot is still recommended for all infants, since early and classic bleeds can occur before feeds are well established.
Answering common questions about safety
Vitamin K has been used for decades. Surveillance and reviews continue to show a strong safety record for the IM dose. The ingredient list is public, and vials do not contain preservatives like thimerosal. The shot is not a vaccine and does not affect the routine vaccine schedule.
Families who want to read primary sources can start with the CDC VKDB pages and the AAP clinical report linked above.
Putting the numbers in context
Asking “how common is vitamin K deficiency in newborns” needs two points. Without any prophylaxis, late bleeds are uncommon but real, and many are brain bleeds. With universal IM vitamin K, late VKDB becomes rare.
Day-one takeaway
Vitamin K deficiency in newborns is preventable. One IM dose at birth covers all VKDB windows and drives late VKDB to very low single-digit rates per 100,000. If you have questions on ingredients or dosing, ask your care team. That is why hospitals standardize the dose. It keeps care simple for families and staff.
How researchers measure rates
Most papers report VKDB per 100,000 live births. That unit helps compare rare events. Studies also separate early, classic, and late windows because timing and triggers differ.
Surveillance can miss cases when bleeding happens outside hospitals or records are incomplete. That means true rates may sit slightly higher than the published figure. Even with that caveat, the pattern stays the same across datasets: IM vitamin K keeps late VKDB to very low single-digit rates.
What happens when no prophylaxis is given
Public health teams have tracked clusters when uptake dips. A well known MMWR report described four late cases in one U.S. city after a rise in refusal. Three babies had brain bleeds. The infants looked well before the event, which is why the shot is offered to every newborn rather than only to babies who seem at risk.
Special situations: preterm and nicu care
Preterm infants also benefit from vitamin K at birth. Dosing may vary by weight, and routes can be adjusted if a baby is unstable. Teams in the nursery or NICU document the dose, route, and time so that the record follows the baby after discharge.
Babies with cholestasis face a higher chance of late VKDB because fat absorption is poor. These infants often need extra oral vitamin K after the birth dose under close follow-up.
Oral regimens used in different countries
Some countries use oral drops instead of an injection. Plans differ by site, from a few post-birth doses to weekly drops for several weeks. Protection depends on taking every dose on time, so reminders and clear tracking help.
Hospitals that offer both plans often steer families to IM dosing because it is one step that covers the months when late VKDB appears. If an oral plan is selected, clinics share a written schedule, set reminders, and check in at well-baby visits.
What families can do today
Before delivery, read your hospital’s newborn care sheet and ask how vitamin K is given on day one. After discharge, keep the birth record where you can find it. If your region uses oral drops, set phone reminders for each dose and bring the bottle to clinic visits so a nurse can check supply and timing.