According to new research, fewer than 48 per cent of women expecting are taking the recommended doses of folic acid and vitamin D.
This is despite official medical advice that taking 400 micrograms of folic acid daily, ideally from the time a woman is trying to conceive through to 12 weeks of pregnancy, can help prevent disorders caused by neural tube defects such as spina bifida.
Earlier this year the UK’s Chief Medical Officers issued a recommendation that all pregnant and breastfeeding women should take 10 micrograms of vitamin D each day to help reduce the growing incidence of babies developing rickets.
Now experts are calling for interventions including the compulsory fortification of flour with folic acid to address the issue and possibly even the provision of free vitamins to all pregnant women.
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The study, Vitamin Supplementation in Pregnancy, from the Division of Women’s Health at King’s College London, shows only between 21 and 48 per cent of pregnant women in the UK take folic acid.
Younger women and those on a lower income have lower take-up rates on the whole.
Yet public awareness is said to be as high as that in Europe and the US, where more women do take the supplements.
Meanwhile there are suggestions that obese women may benefit from higher doses of folic acid in pregnancy, as may pregnant teenagers with “micronutrient-poor diets”.
The report’s authors, doctors Susan Duckworth, Hiten Mistry and Lucy Chappell, argue: “With the high rate of unplanned pregnancy in the UK and an increasingly obese pregnant population vitamin supplementation represents an important public health issue, with potential significant impact on maternal and fetal morbidity and mortality.”
They add: “A varied package of interventions may be needed to increase uptake, particularly for those groups with the lowest use.”
One step, says the study, would be to consider whether “free provision of vitamins to all pregnant women would provide public health rewards that outweigh the costs of treatment”.
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The authors urged the Government to make the fortification of flour with folic acid compulsory, as it already is in the US and other countries.
In 2009 the Scientific Advisory Committee on Nutrition backed a Food Standards Agency Board recommendation for mandatory fortification, while The Medical Research Council – which funded the original trial of folic acid in pregnancy – argues that the measure has prevented thousands of cases of neural tube defects worldwide.
Yet the report points out: “Despite the support from key advisory committees, there has been no further move to make fortification of flour with folic acid mandatory”.
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The study says recent research has also associated taking folic acid in pregnancy with reduced risk of other anomalies such as cardiovascular defects, limb defects and even some childhood cancers such as leukaemia.
On the flip side, the report cautions that supplementation of vitamins A and B, and high-dose vitamins C and E (more than 200mg a day), are not recommended in pregnancy as they can be associated with miscarriage and other health issues.
However, a multivitamin with low doses of vitamin C – below 200mg – can prevent anaemia and is an anti-oxidant.
The report concludes by saying further research is needed to understand the role of other vitamins in improving maternal and infant well-being.