Folic Acid In Late Pregnancy Can Increase Risk Of Allergies

Folic Acid In Late Pregnancy Can Increase Risk Of Allergies

Folic acid has long been recommended to women planning to conceive, and those in early pregnancy.

The supplement works to prevent neural tube defects in babies.

Often, women start to take folic acid if they’re planning a pregnancy.

Others begin to take it as soon as they discover they’re pregnant.

Folic Acid In Late Pregnancy Can Increase Risk Of Allergies

Many women continue to take folic acid throughout pregnancy, as it is usually included in prenatal multi vitamins.

However, new research from Adelaide University has discovered taking folic acid after the first trimester of pregnancy can cause problems for developing babies.

What Did The Study Find?

Past research has shown intrauterine growth restriction (IUGR) can have a protective effect against allergies, including asthma and food allergies.

IUGR means a baby is restricted in growth while still in the womb; this commonly results in low birthweight.

The research team from Adelaide University looked at lambs born to three different groups of sheep:

  • Sheep with a small placenta (restricted)
  • Sheep with a small placenta, given high doses of folic acid in the last month of gestation (restricted supplement)
  • Sheep with a normal placenta and diet (control).

The lambs born from growth restricted pregnancies were less likely to be at risk of developing allergies to egg white proteins than those from normal pregnancies.

However, when sheep with growth restricted pregnancies were fed folic acid during the last trimester, their lambs lost their protection against developing allergies.

What Does This Mean For Pregnant Women?

As a result of the animal testing, the researchers’ advice is women should be counselled about the potential for an increased risk of allergies in their babies if they supplement folic acid beyond the first trimester.

The neural tube develops in the embryo in the very early weeks of pregnancy. Folate has a critical role in assisting cell division, and the body’s demand for the vitamin increases when cell division occurs rapidly, such as at conception and during early pregnancy.

Should I Take Folic Acid?

You might have heard the terms ‘folic acid’ and ‘folate’ being used interchangeably.

It’s very important to know the difference: one is synthetic (folic acid) and the other (folate) is a naturally occurring form of the B vitamin.

Read more about this difference in Folic Acid – What You MUST Know Before You Take It.

Folate is very important for conception and early pregnancy, and it’s particularly necessary because our bodies don’t store it well.

It might seem easy to pop a supplement, but it’s a good idea to find out whether it’s the best choice for you, particularly if you have a genetic mutation of the MTHFR gene.

There’s no doubt folate deficiency can have devastating effects on your developing baby. However synthetic folic acid might also be contributing to the problem.

The best way to ensure you have adequate folate is to eat a varied diet that includes plenty of naturally occurring folate, such as leafy, dark green vegetables and orange and red fruits.

Try to avoid foods that are fortified with folic acid – particularly flour products – as too much consumption can mean your intake of synthetic folic acid is very high throughout pregnancy. This has the potential to reduce protection against allergies after your baby is born.

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Sam McCulloch enjoyed talking so much about birth she decided to become a birth educator and doula, supporting parents in making informed choices about their birth experience. In her spare time she writes novels. She is mother to three beautiful little humans.

One comment

  1. I totally agree on your advice around folate verses folic acid. I would however like to point out that we can not make concussions from just one study. More research needs to be done to see the impacts of the synthetic form on B9, folic acid in the later trimesters. Better still, researching the impact of supplementing in the last trimesters with the natural form of B9, folate as i believe the outcome is likely to be different.

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