A new study has blown the lid off a widely-held belief when it comes to taking folic acid during pregnancy.
The Canadian-led international study, which was published in the British Medical Journal just this week, concluded that high doses of folic acid actually do not protect women against one of the deadliest pregnancy complications - preeclampsia.
Pre-eclampsia is an extremely serious pregnancy condition caused by elevated blood pressure. Each year, 10 million women are affected and 78,000 die from the condition. It is also the second-leading cause of maternal death in Canada. There is no cure, and to save both the mother and baby's life, often the only recourse is premature delivery.
According to Dr. Mark Walker, lead author in the study, professor, and chief of obstetrics, gynecology and newborn care at The Ottawa Hospital, previous studies concluded that high-risk women who take an extra 4 milligrams of folic acid daily cut their chances of developing preeclampsia by about 30 per cent. But scientists wanted to challenge this, and so, this study was born - the only study of its kind in the world.
In a randomized controlled trial spanning five years, 2,300 women who were at risk for preeclampsia were followed across five countries - Canada, the UK, Australia, Jamaica and Argentina. Half of this group were assigned four extra milligrams of folic acid per day, while the other half were given a placebo.
What researchers found surprised them.
"There was absolutely no difference between the group treated with high-dose folic acid and the placebo," said Walker. "Both groups had a pre-eclampsia rate around 14 per cent.”
Despite the results of his study concluding that for women who are at risk for preeclampsia, there is no benefit to being on a high dose of folic acid, Walker notes that pregnant women should not forego low-dose folic acid, which prevents fetal neural-tube defects such as spina bifida. He believes that all women should take folic acid for at least three months prior to conception and that it is "safe and efficacious to take .4 to 1 milligram of folic acid in a multivitamin throughout the pregnancy."
For many experts in this field, these research findings are disappointing. Currently, there are no effective measures to prevent preeclampsia, leaving many families at risk of not being able to start a family.
But there is hope.
Walker and his research team are determined to continue to work towards finding out what solution will eventually prevent this condition from leading to hospitalization during pregnancy, as well as pre-term delivery.
"We plan a couple of more trials and we’re not going to rest until we’ve answered this question,” he said.