WASHINGTON (AFP) — Babies whose mothers had low levels of vitamin B12
just before and after they were conceived could be up to five times more likely
to be being born with a congenital defect, a study said Monday.
Those women, who eat little or no meat or animal-based foods, were the most
likely to have low levels of vitamin B12 and give birth to babies with a neural
tube defect, according to the joint study by Trinity College, Dublin, the Health
Board of Ireland and the US National Institutes of Health.
"Vitamin B12 is essential for the functioning of the nervous system and for the
production of red blood cells," said Duane Alexander, director of the National
Institute of Child Health and Human Development.
"The results of this study suggest that women with low levels of B12 not only
may risk health problems of their own, but also may increase the chance that
their children may be born with a serious birth defect."
It has long been known that mothers-to-be should increase their levels of folic
acid, another B vitamin, to reduce birth defects in their children.
The study, published Monday in the March issue of Pediatrics, said such neural
tube defects affect the brain and spinal cord, such as spina bifida, which can
cause partial paralysis. Another type, anencephaly, is a fatal defect in which
the brain and skull are severely underdeveloped.
The researchers analyzed stored blood samples originally collected during early
pregnancy from three groups of Irish women between 1983 and 1990, when it was
not so common for pregnant women to take vitamin supplements, and compared them
against the records of whose babies were born with congenital defects.
The study showed that pregnant women with less than 250 nanogrammes of vitamin
B12 per liter of blood had a risk 2.5 to three times higher of having a baby
with a neural tube defect.
Women with the lowest levels of vitamin B12 (from zero to 149 nanogrammes a
liter) ran the greatest risk, some five times higher.
Ireland has a high rate of neural tube defects, and NIH scientists have
frequently collaborated with Irish researchers to gain insight into the causes
of this group of disorders, the authors said in a statement.
The results could mean that women and expectant mothers who stick to a vegan
diet may increase the risks of their baby developing some kind of congenital
defect.
"If women wait until they realize that they are pregnant before they start
taking folic acid, it is usually too late," said author James Mills.
Thus he said all women of childbearing age should also consume the recommended
amount of vitamin B12, found in meat, chicken, milk and eggs, whether they are
planning a pregnancy or not.
Critical events in the formation of the brain and spinal column occur very early
in pregnancy "in the first 28 days after conception" before many women even
realize they are pregnant, Mills said.
Source : AFP.
