Pregnancy and child

Fears pregnant women are ignoring folic acid advice

“Women are ignoring expert advice to take folic acid supplements before pregnancy to protect their unborn children,” The Guardian reports. The results of a recent UK study have prompted calls for flour to be fortified with folic acid. 

It has long been known that taking folic acid before getting pregnant can reduce the risk of having a baby with a neural tube defect (birth defects that can affect the brain, spine and spinal cord), such as spina bifida.

Spina bifida is a condition that can result in learning difficulties, paralysis of the lower limbs and bladder and bowel incontinence.

In the UK, it is recommended that women take a 400 microgram folic acid tablet every day while trying to get pregnant and until they are 12 weeks pregnant. If a woman didn't take folic acid before she conceived, it is recommended she starts when she finds out she is pregnant.

Despite these recommendations, a UK study has found that just a third of women report taking folic acid before pregnancy.

The study also found that young women were less likely to take folic acid than older women, and that non-white women were less likely to take folic acid than white women.

The researchers have used these results to call for food in the UK to be fortified with folic acid, to bring the country into line with the US, Canada and Australia.

However, this is a controversial topic and, if actually proposed by UK politicians and policy makers, is likely to be met with considerable resistance, akin to the controversy surrounding the fluoridation of the UK’s water supply.

Where did the story come from?

The study was carried out by researchers from the Wolfson Institute of Preventive Medicine, which is part of Queen Mary University of London. The authors have no support or funding to report and say there are no competing interests.

The study was published in the peer-reviewed journal PLOS One. This is an open access journal, meaning that all research articles, including this one, can be accessed for free.

The study’s results were well-reported in The Guardian, The Daily Telegraph and ITV News.

What kind of research was this?

This was a cross-sectional study, which aimed to survey the extent of folic acid supplementation among women who had antenatal screening for Down’s syndrome and neural tube defects at the Wolfson Institute of Preventive Medicine, London, between 1999 and 2012.

A cross-sectional study is ideal for determining how common something is – in this case, taking folic acid before pregnancy.

What did the research involve?

Women attending Down’s syndrome and neural tube defect screening at the Wolfson Institute of Preventive Medicine were asked if they:

  • had started taking folic acid supplements before pregnancy
  • had started taking folic acid supplements once pregnancy was confirmed
  • had not taken folic acid supplements

The researchers calculated the proportion of women each year who reported taking folic acid supplements before pregnancy.

The researchers also took into account:

  • if women had previously had a neural tube defect pregnancy
  • if women had previously had a Down’s syndrome pregnancy
  • the woman’s ethnicity, weight, age and if she smoked
  • if the women had diabetes
  • if the women had got pregnant using IVF
  • where the women lived
  • time of screening (first or second trimester)

The study aimed to find out if there was a connection between any of these factors and whether they took folic acid.

What were the basic results?

466,860 women screened provided details on folic acid supplementation.

The researchers found that the proportion of women taking folic acid supplements before pregnancy had declined, from 35% over the 1999-2001 period to 31% over 2011-12.

In addition:

  • Younger women were less likely to take folic acid supplements than older women.
  • Just 6% of women aged under 20 took folic acid supplements before pregnancy compared with 40% of women aged 35 and over. 
  • Non-Caucasian women were less likely to take folic acid supplements before pregnancy than Caucasian women. 17% of Afro-Caribbean, 25% of Oriental and 20% of South Asian women took folic acid supplements, compared with 35% of Caucasian women.
  • Women who had had a previous neural tube defect pregnancy were more likely to take folic acid supplements before the current pregnancy (51%, compared to just 30% of women who had not had a previous neural tube defect pregnancy).
  • Women who had had a previous Down’s syndrome pregnancy were more likely to take folic acid supplements before the current pregnancy (54%, compared to 30% of women who had not had a Down’s syndrome pregnancy).
  • Women who had undergone IVF were more likely to take folic acid supplements (83%, compared to just 30% of women who had not had IVF).
  • Women with insulin-dependent diabetes were more likely to take folic acid supplements (38%, compared to 30% of women without insulin-dependent diabetes).
  • Smokers were more likely to take folic acid supplements (33%, compared to just 12% of non-smokers).
  • Women screened in the second trimester were less likely to have taken folic acid supplements before pregnancy than women screened in the first trimester (25% and 33% respectively). The researchers speculate this may be due to the fact a greater proportion of women who had second trimester screenings had unplanned pregnancies.

How did the researchers interpret the results?

The researchers conclude that “the policy of folic acid supplementation is failing and has led to health inequalities. This study demonstrates the need to fortify flour and other cereal grain with folic acid in all countries”.

Conclusion

This was a large cross-sectional study of women who had antenatal screening for Down’s syndrome and neural tube defects in the UK.

It found that the proportion of women taking folic acid supplements is declining, with just a third of women reporting folic acid supplementation before pregnancy.

Young women are less likely to take folic acid than older women, and non-Caucasian women are less likely to take folic acid than Caucasian women.

The researchers are concerned that these differences represent health inequalities (differences in health experienced by certain population groups). 

The researchers have used these results to call for the fortification of food with folic acid.

The Food Standard Agency, the Scientific Advisory Committee on Nutrition and the Chief Medical Officers have all recommended fortification, and this is being considered by UK health ministers.

Opponents cite research that suggests folic acid may increase the risk of developing colorectal cancer. However, the researchers cite evidence that these concerns are "unjustified" because a large meta-analysis found no increased cancer risk in those taking folate supplements.

It is important that women trying to get pregnant take a 400 microgram folic acid tablet every day while trying to get pregnant and until they are 12 weeks pregnant, as this reduces the risk of neural tube defects such as spina bifida. If a woman didn't take folic acid before she conceived, it is recommended she starts as soon as she finds out she is pregnant.

Read more advice about planning your pregnancy.


NHS Attribution