Pregnant women low on the most common form of vitamin E are nearly twice as likely to miscarry as those with adequate levels in their blood, research in Bangladesh shows.
The findings, published online by the American Journal of Clinical Nutrition, suggest that improving the diet of women in impoverished nations or encouraging prenatal supplements of vitamin E could have a direct impact on fertility.
“For nearly a century, we have known about vitamin E and its role in the fertility of animals,” says one of the study’s leaders, Kerry Schulze, associate scientist in international health at the Johns Hopkins University Bloomberg School of Public Health. “To our knowledge, this is the first study in humans that has looked at the association of vitamin E and miscarriage. The findings from this study support a role for vitamin E in protecting the embryo and fetus in pregnancy.”
Women in Bangladesh
Vitamin E is important to proper function of many organs; it is an antioxidant, helping to slow processes that damage cells. The vitamin is found in a variety of foods, but the main source in Bangladesh is believed to be vegetable oils used in cooking.
Researchers analyzed data from 1,605 rural Bangladeshi pregnant women in the JiVitA-1 study, which ran from 2001 to 2007. Blood samples were taken in the first trimester and any miscarriages were recorded on a weekly basis thereafter. Of the 1,605 women in the study, 141, or 8.8 percent, miscarried.
Nearly three of four women in the study were vitamin E deficient, with low levels of alpha-tocopherol, the most active form of the vitamin in the body. About 5.2 percent of women with adequate alpha-tocopherol miscarried in the first or second trimester, compared with 10.2 percent of women with low levels.
The relationship with gamma-tocopherol, the other form of vitamin A tested, went the other way: higher levels were associated with increased miscarriage risk, though to a lesser degree, Schulze says.
Pregnant women in developing countries generally are not given prenatal multivitamins like the type US women typically take before or after becoming pregnant. The current standard of care for developing country mothers-to-be is iron and folic acid supplements because of the proven links between deficiencies of those nutrients and poor pregnancy outcomes.
“The new findings suggest that having pregnant women consume an adequate amount of vitamin E early in pregnancy could be beneficial,” says Abu Ahmed Shamim, associate in international health at the Bloomberg School and lead Bangladeshi author of the study.
Since miscarriages occur early in pregnancy, Shamim says, levels of vitamin E ideally need to be boosted through a diverse diet that includes better vitamin E sources so that women already have what they need when they become pregnant.
“Vitamin deficiencies are considered a form of hidden hunger because they are not readily apparent but they can have huge health consequences,” Schulze says. “What we really want to do is optimize health before women become pregnant, because if they don’t start with a good vitamin E status, they are at a high risk of negative outcomes.”
Schulze says that the study may not be generalizable to higher-income nations where women of childbearing age tend to have better nutritional status.
The Bill and Melinda Gates Foundation and the US Agency for International Development funded the work, with additional support came from the Sight and Life Global Nutrition Research Institute; the Nutralite Health Institute; Foreign Affairs, Trade, and Development Canada; and the government of Bangladesh.
Source: Johns Hopkins University