Dietary quality during pregnancy varies by maternal characteristics in Project Viva: a US cohort.

BACKGROUND: Maternal diet may influence outcomes of pregnancy and childhood, but data on correlates of food and nutrient intake during pregnancy are scarce.
OBJECTIVE: To examine relationships between maternal characteristics and diet quality during the first trimester of pregnancy. Secondarily we examined associations of diet quality with pregnancy outcomes.
METHODS: As part of the ongoing US prospective cohort study Project Viva, we studied 1,777 women who completed a food frequency questionnaire during the first trimester of pregnancy. We used linear regression models to examine the relationships of maternal age, prepregnancy body mass index, parity, education, and race/ethnicity with dietary intake during pregnancy. We used the Alternate Healthy Eating Index, slightly modified for pregnancy (AHEI-P), to measure diet quality on a 90-point scale with each of the following nine components contributing 10 possible points: vegetables, fruit, ratio of white to red meat, fiber, trans fat, ratio of polyunsaturated to saturated fatty acids, and folate, calcium, and iron from foods.
RESULTS: Mean AHEI-P score was 61+/-10 (minimum 33, maximum 89). After adjusting for all characteristics simultaneously, participants who were older (1.3 points per 5 years, 95% confidence interval [CI] [0.7 to 1.8]) had better AHEI-P scores. Participants who had higher body mass index (-0.9 points per 5 kg/m(2), 95% CI [-1.3 to -0.4]), were less educated (-5.2 points for high school or less vs college graduate, 95% CI [-7.0 to -3.5]), and had more children (-1.5 points per child, 95% CI [-2.2 to -0.8]) had worse AHEI-P scores, but African-American and white participants had similar AHEI-P scores (1.3 points for African American vs white, 95% CI [-0.2 to 2.8]). Using multivariate adjusted models, each five points of first trimester AHEI-P was associated lower screening blood glucose level (beta -.64 [95% CI -0.02 to -1.25]). In addition, each five points of second trimester AHEI-P was associated with a slightly lower risk of developing preeclampsia (odds ratio 0.87 [95% CI 0.76 to 1.00]), but we did not observe this association with first trimester AHEI-P (odds ratio 0.96 [95% CI 0.84 to 1.10]).
CONCLUSIONS: Pregnant women who were younger, less educated, had more children, and who had higher prepregnancy body mass index had poorer-quality diets. These results could be used to tailor nutrition education messages to pregnant women to avoid long-term sequelae from suboptimal maternal nutrition.