Researchers in Switzerland checked whether giving newborns vitamin K by mouth (instead of a shot) actually prevents a rare but serious bleeding problem. They looked at nearly 506,000 babies born over 6 years and found only 9 cases of this bleeding disorder. All those babies had parents who refused the vitamin K treatment or had liver problems. The study confirms that Switzerland’s current vitamin K program for healthy newborns is working well and should continue as recommended.

The Quick Take

  • What they studied: Whether Switzerland’s current vitamin K prevention program for newborns is still effective at stopping a rare bleeding disorder called vitamin K deficiency bleeding (VKDB)
  • Who participated: All 505,708 babies born in Switzerland over a 6-year period from 2018 to 2024, tracked through a national health monitoring system
  • Key finding: Only 9 babies developed the bleeding disorder out of over 500,000 births (about 1.78 cases per 100,000 babies). All 9 cases happened in babies whose parents refused vitamin K treatment or who had liver problems. This rate is the same as it was 10-15 years ago, showing the prevention program is working.
  • What it means for you: If you have a healthy newborn in Switzerland and follow the recommended vitamin K program, your baby has excellent protection against this serious bleeding problem. However, if you’re considering refusing vitamin K, it’s important to understand the risks, especially if your baby has any liver issues.

The Research Details

Researchers used Switzerland’s national baby health tracking system to find every case of vitamin K deficiency bleeding that happened between September 2018 and August 2024. This is called ‘surveillance’ - like having a nationwide alert system that catches all serious cases. When a baby was hospitalized with this bleeding problem, doctors reported it to the tracking system. The researchers then looked at all the cases to see what they had in common and whether the current vitamin K prevention program was working.

This approach is powerful because it captures real-world data from an entire country rather than just one hospital or clinic. The researchers compared their findings to similar data from 2005-2011 to see if the prevention program’s effectiveness had changed over time.

This type of nationwide tracking is the best way to know if a prevention program is actually working in real life. Instead of just testing the program in a lab or small group, researchers can see what’s really happening with hundreds of thousands of babies. This gives doctors and parents confidence that the recommendations are based on solid evidence.

This study is strong because it tracked nearly half a million babies across an entire country, making the results very reliable. The researchers used an official health surveillance system designed specifically to catch these rare cases, so they likely found all or nearly all cases that occurred. The main limitation is that vitamin K deficiency bleeding is so rare that even with 500,000 babies, only 9 cases appeared - this small number makes it harder to spot patterns. Additionally, the study relied on doctors reporting cases, so a few cases might have been missed if they weren’t hospitalized or reported.

What the Results Show

Over the 6-year study period, Switzerland recorded 9 cases of vitamin K deficiency bleeding among 505,708 live births. This works out to about 1.78 cases per 100,000 babies born. To put this in perspective, this is an extremely rare condition - you’d need to look at about 56,000 babies to expect to find one case.

Every single one of the 9 babies who developed this bleeding problem had something in common: either their parents had refused the vitamin K treatment, or the baby had an unrecognized liver problem (cholestasis), or both. None of the babies who received the recommended vitamin K treatment developed the bleeding disorder.

When researchers compared these numbers to data from 2005-2011 (about 10-15 years earlier), they found almost identical rates of the bleeding disorder. This means the prevention program hasn’t lost its effectiveness over time - it’s still working just as well as it did over a decade ago.

The study highlighted that parental refusal of vitamin K treatment is becoming more common, which is concerning because it’s the main factor in cases that do occur. Additionally, the research emphasizes that unrecognized liver problems in newborns are an important risk factor. Babies with liver issues may not process vitamin K properly, even if they receive the treatment. This suggests that identifying babies with liver problems early is crucial for their safety.

This research confirms what doctors have believed based on earlier studies - that Switzerland’s vitamin K prevention program, introduced in 2003, continues to be highly effective. The program uses oral (by mouth) vitamin K rather than injections, which some parents prefer. The fact that the rate of bleeding disorder hasn’t increased despite more parents refusing treatment shows that the program protects the majority of babies whose parents do accept it. This aligns with international research showing that both oral and injected vitamin K are effective when properly administered.

The main limitation is that vitamin K deficiency bleeding is so rare that even studying half a million babies only found 9 cases. With such small numbers, it’s harder to be completely certain about patterns or to predict future trends. Additionally, the study depends on doctors reporting cases to the surveillance system - if some cases weren’t hospitalized or weren’t reported, they wouldn’t be counted. The study also only looked at Switzerland, so results might differ slightly in other countries with different healthcare systems or populations. Finally, the study couldn’t examine all possible factors that might influence outcomes, such as breastfeeding practices or dietary factors in detail.

The Bottom Line

For healthy newborns in Switzerland: The current vitamin K prevention program (2 mg given by mouth at 4 hours after birth, at day 4, and at week 4) is strongly recommended and highly effective. Parents should follow this program unless there are specific medical reasons not to. For babies with known liver problems or cholestasis: Extra monitoring and possibly different vitamin K dosing may be needed - discuss this with your pediatrician. For parents considering refusing vitamin K: Understand that while the risk is low for healthy babies, refusing this simple, safe treatment removes important protection against a serious bleeding problem.

All parents of newborns in Switzerland should care about this research. It’s especially important for parents who are considering refusing vitamin K treatment to understand the real risks. Healthcare providers should use this information to educate parents about why the program matters. Parents of babies with liver problems or cholestasis should be particularly attentive to vitamin K recommendations. This research is less directly relevant to families outside Switzerland, though the findings support similar programs in other countries.

Vitamin K protection begins immediately after the doses are given. The three-dose schedule (at 4 hours, day 4, and week 4) is designed to provide protection throughout the first 6 months of life, when vitamin K deficiency bleeding is most likely to occur. Most babies who will develop this problem show signs within the first month of life, so the early doses are particularly important.

Want to Apply This Research?

  • Track vitamin K administration dates: Record the exact dates and times your newborn receives each of the three vitamin K doses (4 hours after birth, day 4, and week 4). Set reminders for each dose to ensure none are missed. Note any parental concerns or questions about the treatment.
  • Use the app to create a simple checklist for vitamin K doses and mark each one off as completed. Set notifications 24 hours before each scheduled dose. If you have concerns about vitamin K, use the app to document your questions and discuss them with your pediatrician at the next visit rather than delaying or refusing treatment.
  • In the app, create a health record noting that your baby received the complete vitamin K prevention series. If your baby shows any unusual bleeding (such as blood in stool, vomit, or unusual bruising), immediately log this and contact your healthcare provider. Keep this record accessible for future medical visits.

This research summary is for educational purposes and should not replace professional medical advice. Vitamin K treatment decisions should be made in consultation with your pediatrician or healthcare provider, who can assess your individual baby’s health status and risk factors. If you have concerns about vitamin K treatment or your baby shows signs of unusual bleeding, contact your healthcare provider immediately. This summary reflects research specific to Switzerland’s healthcare system and guidelines; recommendations may differ in other countries.