Diet and folic acid can influence pregnancy outcomes

Flinders UniversityOct 8 2020

Healthy dietary choices are not only important for expectant mothers during the early months of pregnancy but equally important in the months prior to conception.

Fast food consumption prior to pregnancy was found to be a risk factor for gestational diabetes, while low consumption of green leafy vegetables and fruit was found to increase the risk for several pregnancy complications including gestational diabetes, spontaneous pre-term birth and having a small for gestational age baby.

Researchers at Flinders University’s College of Medicine and Public Health have studied genetic and lifestyle factors that could affect pregnancy health and outcome.

The study, led by a world-renowned placental biologist and pregnancy expert Professor Claire Roberts, involved 3196 women with a first-time pregnancy, recruited into the SCOPE Study in Adelaide and Auckland between 2005 and 2008.

Professor Roberts’ team found that both maternal and paternal genes involved in folate and folic acid metabolism influenced pregnancy outcomes, including preeclampsia, gestational hypertension and spontaneous pre-term birth.

While there is not much that can be done with the genetic hand women are dealt, there are modifiable lifestyle factors, such as diet, that women can have control over when it comes to their pregnancy. We know from our previous research that mothers with folate deficiency are more likely to have a number of pregnancy complications, and this study supports the benefits of increasing folate levels via green vegetable consumption to support pregnancy health.”

Claire Roberts, Professor, Flinders University

Women who are planning to conceive are recommended to take folic acid supplementation at least one month before conception and during the first few months of pregnancy to minimize the potential for folate deficiency and reduce the risk of having a baby with a neural tube defect.

The article, “Maternal folate, one carbon metabolism and pregnancy outcomes,” (2020) by Jankovic-Karasoulos T, Furness DL, Leemaqz SY, Dekker GA, Grzeskowiak LE, Grieger JA, Andraweera PH, McCullough D, McAninch DC, McCowan LM, Bianco-Miotto T and Roberts CT has been published in Maternal and Child Nutrition. https://doi.org/10.1111/mcn.13064.

However, in this study, conducted before the introduction of folic acid fortification mandate in Australia, women who developed gestational hypertension and gestational diabetes mellitus had higher serum folate levels at 15 weeks’ gestation compared to women who had an uncomplicated pregnancy.

Researchers say further studies are needed to assess the relevance of the association between maternal circulating folate levels and gestational hypertension and potentially gestational diabetes, particularly in light of the mandatory folic acid fortification program. Interestingly, this has coincided with a steep rise in the incidence of gestational diabetes in Australia. In South Australia, gestational diabetes was at 5.5% in 2009 but by 2017 it had risen to 14%.

The Australian government’s 2009 decision to implement mandatory folic acid fortification of flour for commercial bread-making and pastries has resulted in increased folic acid consumption by the general Australian public. As a result, pregnant Australian women are now consuming higher levels of folic acid through a combination of fortified diets and micronutrient supplementation.

Due to this shift, Professor Roberts’ Pregnancy Health and Beyond research team is now studying the effects of too much folic acid can have during pregnancy and is trying to determine what effects this will have on not only pregnancy health, but also the health of the mother and her baby later in life.

From our current research, we know that both serum and red blood cell folate levels in pregnant women recruited in Adelaide within the past few years are up to 4 times higher than those measured in women from this study. Because few women are now folate deficient during early pregnancy, we may need to re-focus on understanding the effects of folate excess.”

Dr Tanja Jankovic-Karasoulos, Study researcher