Bid to end birth defects

Press, 6 March 1980, Page 17

Bid to end birth defects

By

OLIVER GILLIE,

‘‘Sunday Times,” London

Doctors from England and Northern Ireland have discovered a way of preventing spina bifida and anencephaly — the two commonest birth defects in Britain. On average, one baby in 200 is affect-

ed in England, but in. Scotland and Northern Ireland the figure is one in 100, and so the condition has been called the curse of the Celts.

Now, the condition can be prevented by certain vitamins being taken for at least a month before conception and up to the second missed menstrual period. -X Vitamin deficiency has long been suspected as the cause of spina bifida and anencephaly because the condition is some three times more common in mothers on low incomes. And it has been known since 1951 that deficiency of a B vitamin, folic acid, causes malformations of the central nervous systems of animals. This and other vitamins — A, B2 and C — have been found to 5 be present in lower

quantities in the blood of women on low incomes. These vitamins are essential for the • normal growth and division of cells. During the first few weeks following conception the foetus grows rapidly and one of the

first distinct parts to be formed is the spinal cords. If this growth is interrupted the spinal column will not form properly. Then, if the spinal tube does not close properly at the top end, the brain is not formed — this is anencephaly. If the tube is not formed properly at the bottom end then the spine is left exposed — and this is spina bifida. Together, they are called neural tube defects.

Now Professor Richard Smithells, of Leeds University, and a team of seven others have been able to prevent these defects by persuading vulnerable women to take a standard

multi-vitamin preparation called Pregnavite Forte F, manufactured by the pharmaceutical firm Bencard. Smithells instructed the women to take the preparation for four weeks before conception to stock up their bodies and to

continue to take it until they had missed at least two periods. This meant that tneir bodies were getting plenty of the vitamin at just the time when the foetuses were developing their spinal cords. .. Smithells’s team gave the drug to women who had previously had at least one child with a neural defect because the chances of their having another w’ith the same condition are above average. ' The women were checked during pregnancy by amniocentesis — a needle pushed into the womb to take a sample of the liquid. If the foetus has a neural tube defect,

spinal fluid leaks into the womb and can be detected in the specimen. Foetuses with neural tube defects were aborted when detected. Only one baby with a neural tube defect was bom to 178 mothers who took the vitamins. The remainder were normal. By contrast, 13 babies or foetuses with the condition delivered to 260 comparable women who were not given the vitamins. This was the normal recurrence rate of the condition: 5 per cent. It may be that further research will show that some women should take the vitamin for longer before pregnancy. This might then allow for the unforeseen — mild illness, for example, can produce a marked reduction of vitamins in the blood. The high frequency of neural tube defects among Celts highlights the general deficiency in Scottish and Irish diets of fresh, leafy vegetables, fruit and wholemeal bread.