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Newborn infants routinely
receive a vitamin K shot after
birth in order to prevent (or
slow) a rare problem of bleeding
into the brain weeks after
birth. Vitamin K promotes blood
clotting. The fetus has low
levels of vitamin K as well as
other factors needed in
clotting. The body maintains
these levels very precisely.1
Supplementation of vitamin K to
the pregnant mother does not
change the K status of the
fetus, confirming the importance
of its specific levels.
Toward the end of gestation, the
fetus begins developing some of
the other clotting factors,
developing two key factors just
before term birth.2
It has recently been shown that
this tight regulation of vitamin
K levels helps control the rate
of rapid cell division during
fetal development. Apparently,
high levels of vitamin K can
allow cell division to get out
of hand, leading to cancer.
What's
the Concern?
The problem of bleeding into the
brain occurs mainly from 3 to 7
weeks after birth in just over 5
out of 100,000 births (without
vitamin K injections); 90% of
those cases are breastfed
infants,3 because
formulas are supplemented with
unnaturally high levels of
vitamin K. Forty percent of
these infants suffer permanent
brain damage or death.
The cause of this bleeding
trauma is generally liver
disease that has not been
detected until the bleeding
occurs. Several liver problems
can reduce the liver's ability
to make blood-clotting factors
out of vitamin K; therefore
extra K helps this situation.
Infants exposed to drugs or
alcohol through any means are
especially at risk, and those
from mothers on anti-epileptic
medications are at very high
risk and need special attention.
Such complications reduce the
effectiveness of vitamin K, and
in these cases, a higher level
of available K could prevent the
tragic intracranial bleeding.
This rare bleeding disorder has
been found to be highly
preventable by a large-dose
injection of vitamin K at birth.
The downside of this practice
however is a possibly 80%
increased risk of developing
childhood leukemia. While a few
studies have refuted this
suggestion, several tightly
controlled studies have shown
this correlation to be most
likely.4,5 The most
current analysis of six
different studies suggests it is
a 10 or 20% increased risk. This
is still a significant number of
avoidable cancers.6
Apparently the cell division
that continues to be quite rapid
after birth continues to depend
on precise amounts of vitamin K
to proceed at the proper rate.
Introduction of levels that are
20,000 times the newborn level,
the amount usually injected, can
have devastating consequences.
The Newborn's Diet
Nursing raises the infant's
vitamin K levels very gradually
after birth so that no
disregulation occurs that would
encourage leukemia development.
Additionally, the clotting
system of the healthy newborn is
well planned, and healthy
breastfed infants do not suffer
bleeding complications, even
without any supplementation.7
While breastfed infants
demonstrate lower blood levels
of vitamin K than the
"recommended" amount, they show
no signs of vitamin K deficiency
(leading one to wonder where the
"recommended" level for infants
came from). But with vitamin K
injections at birth, harmful
consequences of some rare
disorders can be averted.
Infant formulas are supplemented
with high levels of vitamin K,
generally sufficient to prevent
intracranial bleeding in the
case of a liver disorder and in
some other rare bleeding
disorders. Although formula
feeding is seen to increase
overall childhood cancer rates
by 80%, this is likely not
related to the added vitamin K.
The Numbers
Extracting data from available
literature reveals that there
are 1.5 extra cases of leukemia
per 100,000 children due to
vitamin K injections, and 1.8
more permanent injuries or
deaths per 100,000 due to brain
bleeding without injections.
Adding the risk of infection or
damage from the injections,
including a local skin disease
called "scleroderma" that is
seen rarely with K injections,8
and even adding the possibility
of healthy survival from
leukemia, the scales remain
tipped toward breastfed infants
receiving a prophylactic vitamin
K supplementation. However,
there are better options than
the .5 or 1 milligram injections
typically given to newborns.
A Better Solution
The breastfed infant can be
supplemented with several low
oral doses of liquid vitamin K9
(possibly 200 micrograms per
week for 5 weeks, totaling 1
milligram, even more gradual
introduction may be better).
Alternatively, the nursing
mother can take vitamin K
supplements daily or twice
weekly for 10 weeks.
(Supplementation of the pregnant
mother does not alter fetal
levels but supplementation of
the nursing mother does increase
breastmilk and infant levels.)
Either of these provides a much
safer rate of vitamin K
supplementation. Maternal
supplementation of 2.5 mg per
day, recommended by one author,
provides a higher level of
vitamin K through breastmilk
than does formula,10
and may be much more than
necessary.
Formula provides 10 times the
U.S. recommended daily
allowance," and this RDA is
about 2 times the level in
unsupplemented human milk. One
milligram per day for 10 weeks
for mother provides a cumulative
extra 1 milligram to her infant
over the important period and
seems reasonable. Neither mother
nor infant require
supplementation if the infant is
injected at birth.11
The
Bottom Line
There is no overwhelming reason
to discontinue this routine
prophylactic injection for
breastfed infants. Providing
information about alternatives
to allow informed parents to
refuse would be reasonable.
These parents may then decide to
provide some gradual
supplementation, or, for an
entirely healthy term infant,
they may simply provide diligent
watchfulness for any signs of
jaundice (yellowing of eyes or
skin) or easy bleeding.
There appears to be no harm in
supplementing this vitamin in a
gradual manner however.
Currently, injections are
provided to infants intended for
formula feeding as well,
although there appears to be no
need as formula provides good
gradual supplementation.
Discontinuing routine injections
for this group alone could
reduce cases of leukemia.
One more curious look at
childhood leukemia is the
finding that when any nation
lowers its rate of infant
deaths, their rate of childhood
leukemia increases.12
Vitamin K injections may be
responsible for some part of
this number, but other factors
are surely involved, about which
we can only speculate.
Notes
1. L.G.
Israels et al., "The riddle of
vitamin K1 deficit in the
newborn," Semin Perinatol 21,
no. 1 (Feb 1997): 90-6.
2. P.
Reverdiau-Moalic et al.,
"Evolution of blood coagulation
activators and inhibitors in the
healthy human fetus," Blood
(France) 88, no. 3 (Aug 1996):
900-6.
3. A.H. Sutor
et al., "Late form of vitamin K
deficiency bleeding in Germany,"
Klin Padiatr (Germany) 207, no.
3 (May-Jun 1995): 89-97.
4. L. Parker
et al., "Neonatal vitamin K
administration and childhood
cancer in the north of England:
retrospective case-control
study," BMJ (England) 316, no.
7126 (Jan 1998): 189-93.
5. S.J.
Passmore et al., "Case-control
studies of relation between
childhood cancer and neonatal
vitamin K administration," BMJ
(England) 316, no. 7126 (Jan
1998): 178-84.
6. E. Roman et
al., "Vitamin K and childhood
cancer: analysis of individual
patient data from six
case-control studies," Br J
Cancer (England) 86, no. 1 (Jan
2002): 63-9.
7. M. Andrew,
"The relevance of developmental
hemostasis to hemorrhagic
disorders of newborns," Semin
Perinatol 21, no. 1 (Feb 1997):
70-85.
8. E. Bourrat
et al., "[Scleroderma-like patch
on the thigh in infants after
vitamin K injection at birth:
six observations]," Ann Dermatol
Venereol (France) 123, no. 10
(1996): 634-8.
9. A.H. Sutor,
"Vitamin K deficiency bleeding
in infants and children," Semin
Thromb Hemost (Germany) 21, no.
3 (1995): 317-29.
10. S.
Bolisetty, "Vitamin K in preterm
breast milk with maternal
supplementation," Acta Paediatr
(Australia) 87, no. 9 (Sep
1998): 960-2.
11. K.
Hogenbirk et al., "The effect of
formula versus breast feeding
and exogenous vitamin K1
supplementation on circulating
levels of vitamin K1 and vitamin
K-dependent clotting factors in
newborns," Eur J Pediatr 152,
no. 1 (Jan 1993): 72-4.
12. A.
Stewart, "Etiology of childhood
leukemia: a possible alternative
to the Greaves hypothesis," Leuk
Res (England) 14, nos. 11-12
(1990): 937-9.
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