New research from Flinders University has raised questions about the amount of folic acid some women take during early pregnancy, after researchers found a possible link between higher supplementation and vaginal bleeding.

The study examined more than 2,400 first-time mothers in South Australia and compared pregnancy data collected before and after Australia introduced mandatory folic acid fortification of bread-making flour.

Researchers found that women taking 800 micrograms or more of folic acid a day were more likely to experience spotting or mild vaginal bleeding during the first 16 weeks of pregnancy. The association appeared particularly strong among women carrying male babies.

In pregnancies involving boys, researchers found that the likelihood of vaginal bleeding was more than twice as high among women taking high-dose folic acid compared with those who did not take supplements.

The findings do not mean women should stop taking folic acid. The vitamin remains an important part of pregnancy care because it helps prevent neural tube defects, including serious birth defects affecting the brain and spinal cord.

Instead, researchers say the study highlights the import.th and placental problems.

Professor Claire Roberts, a senior researcher on the study, said the results suggest that the relationship between folic acid intake and pregnancy health may be more complex than previously understood.

The researchers stress that the findings show an association, not proof that high-dose folic acid directly causes bleeding. More research is needed to understand the biological mechanisms involved and determine whether supplementation guidelines should be refined.

For now, experts advise pregnant women to follow the recommendations of their doctors or healthcare providers rather than changing their folic acid intake based on this study alone.

Source: Flinders University research, published in Reproductive Health.