One of the most important nutrients for pregnant women to get while carrying a baby is folic acid. Health officials already knew it was good for babies' brains, but it may help their hearts too.
A recent study found that women were half as likely to have a newborn with a heart defect if they took folic acid supplements during pregnancy.
Folic acid is a B vitamin that helps a growing baby's neural tube close in the first month of pregnancy. The neural tube becomes a baby's spinal cord and brain.
Folic acid is included in standard prenatal vitamins for pregnant women.
The study, led by Xiaohong Li, of the National Center for Birth Defect Monitoring at Sichuan University in China, looked for links between heart defects in newborns and whether their mothers had taken folic acid.
The researchers compared 358 children who were born with heart defects to 422 children who were born without heart defects and were otherwise healthy.
The women underwent extensive interviews, including questions about whether they took supplements, their socioeconomic status, their lifestyle behaviors, their work environment, their history of pregnancy, their history of illness, past medications they had taken, how often they ate certain foods and similar questions.
The researchers found that women who reported taking folic acid supplements were half as likely than the women who did take folic acid supplements to have a baby with a heart defect.
The reduced risk for heart defects in their babies only showed up for women who took folic acid for at least one month or longer.
Women who took folic acid supplements for less than a month at any time during their pregnancy did not have a reduced risk for having a baby with a heart defect.
Meanwhile, the mothers who took folic acid supplements for at least three months, starting before they conceived their child, were even less likely (79 percent lower risk) to have a baby with a heart defect, compared to those who did not take folic acid supplements.
"Beginning folic supplementation before pregnancy and supplementing folic for a longer time period appear to be more effective in reducing congenital heart defects," the researchers concluded.
The study was published in the June issue of the journal Preventive Medicine. The research was funded by the National Basic Research Program of China, the Program for Changjiang Scholars and Innovative Research Team in University and the National Science Foundation. The authors declared no conflicts of interest.