Two hundred-ninety women (aged 21 to 38 years) with low-risk pregnancies were randomly assigned to continue their usual diet (control group) or to adopt a cholesterol-lowering diet (intervention group) that promoted fish, low-fat meats and dairy products, oils, whole grains, fruits, vegetables, and legumes from gestational week 17-20 until delivery. Maternal total- and LDL-cholesterol levels were lower in the intervention group than in the control group (p < 0.01), but lipid levels were similar in the neonates from the two groups. The incidence of premature delivery (< 37 weeks) was 0.7% in the intervention group and 7.4% in the control group (relative risk = 0.10; 95% confidence interval, 0.01-0.77). The incidence of other pregnancy complications was similar in the two groups. The authors concluded that consumption of a cholesterol-lowering diet reduced the incidence of preterm delivery in women with low-risk pregnancies.

Comment: The diet used in this study contained a wide variety of healthful foods. The fact that it was a cholesterol-lowering diet may not be relevant to its beneficial effect on pregnancy outcome. Perhaps the correct conclusion is that a diet containing high-quality macronutrients and abundant amounts of micronutrients favorably influences pregnancy outcome. Eggs are high in cholesterol, but they also contain high-quality protein and a large amount of choline, a nutrient that is crucial for fetal and infant brain development. The results of the new study should not lead to the conclusion that pregnant women should avoid eating eggs.

Khoury J, et al. Effect of a cholesterol-lowering diet on maternal, cord, and neonatal lipids, and pregnancy outcome: a randomized clinical trial. Am J Obstet Gynecol. 2005;193:1292-1301.