By increasing the amount of fiber in the diet during early pregnancy, the risk of preeclampsia in later pregnancy falls, according to a report in the American Journal of Hypertension.

The results suggest that a higher amount of dietary fiber achieves this effect, at least in part, by reducing pregnancy-associated elevated blood fats, Dr. Chunfang Qiu, from the Swedish Medical Center in Seattle, Washington, and colleagues state.

Preeclamspia is a potentially serious condition that occurs in pregnancy characterized by a spike in blood pressure, protein in the urine and an increase risk of having an infant to be born prematurely.

There is considerable epidemiologic evidence for a reduced risk of high blood pressure with diets that are high in fiber, the authors note. However, relatively few studies have focused on the impact that dietary fiber during early pregnancy has on the risk of developing preeclampsia.

The investigators used a food-frequency survey conducted with 1,538 pregnant Washington State residents. The women’s diets were assessed for fiber content 3 months before pregnancy and during the first trimester.

After analyzing the data, the researchers found that women with the highest amounts of fiber in their diets (21.2 grams or more per day) during both assessment periods were 72 percent less likely to develop preeclampsia than those with the lowest levels (less than 11.9 grams per day).

Similar associations were seen when the researchers restricted the analysis to consumption of water-soluble fiber or insoluble fiber.

Blood fat profiles also improved with high fiber intake. Those with the highest levels of fiber consumption had average triglyceride levels that were lower and HDL-cholesterol levels that were higher compared with women with the lowest levels of dietary fiber.

“Taken together with previously published literature, these results suggest important health benefits of increased fiber consumption before and during early pregnancy. If confirmed by other studies, our findings may motivate increased efforts aimed at exploring lifestyle approaches, particularly dietary approaches, to lower the risk of preeclampsia,” the authors conclude.

SOURCE: American Journal of Hypertension, July 17, 2008 online issue