Vitamin K for Newborns
Vitamin K deficiency is a rare but preventable disease. However, treatment for this deficiency has come under fire lately as being possibly linked to an increased risk of leukemia. But is this risk fact or fiction? If your newborn recieves a vitamin K treatment at birth, is she more likely to develop leukemia?
Why is Vitamin K Given to Newborns?
There is a rare disease called Vitamin K deficiency bleeding, which occurs in approximately 1 in 10,000 babies. In about half of babies who suffer this bleeding problem after the first week of life, many will die or sustain significant brain-damage due to the disease, because of bleeding into the brain.
It occurs almost exclusively in breastfed babies and is almost completely preventable by giving extra vitamin K after birth.
Which Babies are Most at Risk of this Bleeding Problem?
The early type of bleeding is a particular risk for babies whose mothers were on certain drugs during pregnancy, such as anticonvulsants (for epilepsy). The late bleeding disease is more common in babies who are born premature, who have had a complicated delivery (such as a breech delivery, forceps or ventouse), or those who have liver disease or difficulty absorbing feeds. Many babies who go on to have more serious bleeding problems suffer smaller bleeds from the skin, nose or mouth in the weeks before this.
Why Not Just Give Vitamin K to Those at High Risk of Bleeding?
Unfortunately, in about 1/3 of cases, the vitamin K deficiency bleed occurs without prior warning or risk factor. It has been estimated that if vitamin K were only given to high risk babies, among the 800,000 or so annual births in the UK, there might be:
- 60 to 80 babies who suffer a bleed
- 15 to 20 babies suffering a bleed into the brain
- 4 to 6 babies who die from the bleed into the brain
- 10 to 20 babies who may be brain damaged because of the bleeding
What is the Controversy About Vitamin K?
Since the 1960's, vitamin K has been used widely in the UK, throughout Europe and the US, being given as a single injection just after birth. This is cheap and effective, with no recorded treatment failures, even in babies with liver disease, who are at most risk.
Concerns about the safety of this arose in the early 1990's when two papers were published in the medical literature, suggesting an association between vitamin K injection and childhood leukaemia (a blood cancer). The papers looked at children with leukaemia and checked how many of them had received vitamin K injection compared to children without leukaemia. They found an increased risk of leukaemia by a factor of about 1.8.
Following this very unexpected finding, lots of other comparisons were made throughout the world to see if this was indeed a true increase in risk or just a chance happening in this group. Studies from the UK, USA, Germany and Sweden found no evidence to support these findings. A Danish study followed all children born in Denmark over a 40 year period from 1945 and compared the leukaemia rates in those receiving no vitamin K, vitamin K by mouth and vitamin K injection and found no difference.
More recently a Scottish study looked at over 400 children aged up to 14 years with cancers and found no association between vitamin K injection and any cancer. Two more studies were published this year containing a total of 4000 cases of childhood cancers, demonstrating no association with vitamin K usage.
Which is the Best Way for the Newborn to Receive Vitamin K?
After the initial concens about vitamin K injection and before the many more reassuring studies, the national policy in Germany and Australia changed over to the 'by mouth' or oral regime for vitamin K. This means giving one dose at delivery, one at 7 days of age, and a further one at 28 days to achieve the same protection as a single injection just after delivery. After this change in policy, an increase in the rate of vitamin K deficiency bleeding was found, affecting about 1 in 100,000 infants.
This failure of the oral vitamin K to work was probably in part due to not having a specific oral form of the drug available, as it is now. It is also, in some cases, due to a failure to complete the course. If the newer vitamin K oral formulation (Konakion MM) is taken as an extended course, at the correct times, it is almost certainly as successful in preventing bleeding problems as the single injection.
What do the 'Experts' Say?
- A joint UK Medicines Control Agency, Committee on the Safety of Medicines and Department of Health expert group has concluded that overall, the available data do not support an increased risk of cancer, including lukaemia, caused by vitamin K.
- The American Academy of Paediatrics concludes 'vitamin K injection prevents a life-threatening disease of the newborn and the risks of cancer are unproven and unlikely' and recommends a single injection for all neonates.
- Extended oral courses of vitamin K are routinely advised in Germany, Denmark, The Netherlands and Australia.
So What Should I Do?
In summary, the options you have are whether to have vitamin K for your baby at all and, should you decide to do so, whether to have it as a single injection just after delivery, or as an extended oral course. If you are bottlefeeding your baby, the final dose will not be necessary (as vitamin K is added to formula feed).
The evidence on the risk of leukaemia associated with vitamin K injection does not suggest an increased risk, but it is not possible to completely, 100% exclude this at present. The risk of the vitamin K deficient bleeding disease is well known and almost 100% preventable by additional vitamin K, by either injection or oral treatment.