Seattle, Washington - Women who consume a high amount of dietary fiber during early pregnancy have a reduced risk of subsequent preeclampsia compared with those who eat little, according to a new prospective study [1].

For those with the highest intake, there was a 70% reduction in preeclampsia compared with those who had the lowest fiber intake, Dr Chunfang Qiu (Swedish Medical Center, Seattle, Washington) and colleagues report online July 17, 2008 in the American Journal of Hypertension.

Their results also show that dietary fiber may attenuate pregnancy-associated dyslipidemia, an important clinical characteristic of preeclampsia. "To our knowledge, we are the first to examine the relationship between maternal plasma lipid concentrations and habitual fiber intake during pregnancy," they state. "These results suggest important health benefits of increased fiber consumption before and during early pregnancy."

Preeclampsia, a vascular disorder of pregnancy, is associated with potentially lethal complications, including placental abruption, disseminated intravascular coagulation, cerebral hemorrhage, hepatic failure, and acute renal failure, say Qiu et al. Established risk factors for preeclampsia include obesity, family history of type 2 diabetes and/or essential hypertension, and diets low in antioxidants, fruits, and vegetables—risk factors similar to those typically reported for cardiovascular disorders.

The researchers note that only three prior studies have directly evaluated preeclampsia risk in relation to maternal fiber intake and that the results from these have been inconsistent.

Using women participating in an ongoing prospective cohort study, Omega, they assessed maternal dietary fiber intake in early pregnancy and its association with subsequent preeclampsia risk. The 1538 pregnant women participating completed a 121-item food frequency questionnaire.

The researchers also evaluated the influence of fiber on maternal plasma lipid and lipoprotein concentrations among the study population. This secondary objective was inspired by reports showing the benefits of dietary fiber on the plasma lipid profile in numerous studies of men and nonpregnant women, they note.

Fiber intake was associated with reduced preeclampsia risk. After adjustment, the relative risk of preeclampsia for women in the highest quartile (>21.2-g fiber/day) vs the lowest quartile (<11.9 g/day) was 0.28.

Associations of similar magnitude were seen when they looked at highest vs lowest quartiles of water-soluble fiber (RR 0.30) and insoluble fiber (RR 0.35), respectively.

And mean triglyceride concentrations were lower (-11.9 mg/dL, p=0.02) and HDL-cholesterol concentrations higher (+2.63 mg/dL, p=0.09) for women in the highest quartile vs those in the lowest quartile of fiber intake.

"This prospective study provides additional evidence of reduced preeclampsia risk associated with higher maternal dietary fiber intake in early pregnancy," Qiu et al state. "Fiber intake was also inversely related with maternal triglycerides and positively related with HDL concentrations (although to a lesser degree) during early pregnancy.

"Taken together with previously published literature, [and] 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," they conclude.