The Dietary Approaches to Stop Hypertension (DASH) diet has been shown to improve cardiometabolic outcomes in non-pregnant populations. Little is known regarding the impact of this diet on health during pregnancy. The objective of this research is to examine associations of adherence to the DASH diet with hypertensive disorders of pregnancy (HDP) and other pregnancy outcomes.
We conducted analyses with data that came from 1760 women in Project Viva, a Boston-area longitudinal cohort recruited in early pregnancy 1999-2002. We derived a DASH score using data from a food frequency questionnaire (FFQ) administered at median 11.1 weeks gestation. Next, we used multivariable linear regression models that accounted for the woman's age at enrollment, pre-pregnancy body mass index (BMI), education, smoking habits, race/ethnicity, gestational weight gain (GWG) up until the time of the FFQ, and total energy intake to examine associations of the DASH score with HDP, gestational diabetes, preterm delivery (<37 weeks), birth size, and GWG from FFQ to delivery. Models for HDP and GDM were additionally mutually adjusted for each other. Because pre-pregnancy weight status may modify these relationships, we tested for interactions between pre-pregnancy BMI and the DASH score.
Mean ± SD age of the women was 32.2 ± 4.9 years; 71.9% were white. Overall, the DASH diet score (mean: 24.0, SD: 5.0) was not associated with any of the pregnancy outcomes or complications. However, we found a positive association between the DASH diet and subsequent GWG among women who were obese before pregnancy (0.19 [95% CI: 0.05, 0.34], P ≤ 0.05 kg higher GWG per 1 unit DASH score).
Adherence to DASH diet during early pregnancy does not appear to be protective against HDP or other adverse pregnancy outcomes.