Diet During Pregnancy and Risk of Preeclampsia or Gestational Hypertension
Introduction
Hypertensive disorders of pregnancy, including preeclampsia (PE) and gestational hypertension (GH), are associated with substantial morbidity and mortality for both mother and child. Most established risk factors for PE or GH, including maternal age, race/ethnicity, parity, and previous hypertension or PE, are not modifiable (1). During the past two decades, a number of studies have examined whether maternal diet during pregnancy might influence risk for PE or GH.
A systematic review of randomized clinical trials demonstrated a reduction in the relative risk for the development of high blood pressure (0.58, 95% confidence interval [95% CI]: 0.22–0.97) and PE (0.35, 95% CI 0.20–0.60) with supplementation of at least 1 g/day of calcium during pregnancy (2). However, the largest trial, the Calcium for Preeclampsia Prevention trial, did not find a benefit of calcium supplementation on PE or GH (3). Observational studies have suggested potential benefits of other nutrients, including n-3 fatty acids or fish oils 4, 5, 6, magnesium (7), and antioxidant vitamins (8), and a potential risk of trans fatty acids (9), based upon either dietary intake or levels of biomarkers among women who develop PE. However, not all observational studies and randomized trials have shown any effect of these nutrients 10, 11, 12, 13, 14, 15, 16, 17. In particular, recent trials have not supported a benefit of vitamins C and E 18, 19, 20.
Both randomized trials and observational studies are valuable in studying nutrient-outcome associations. Although experimental trials can minimize confounding and demonstrate causality, observational studies can provide information about a range of nutrient intake and about nutrients derived from foods as well as from supplements. The purpose of this observational study was to examine associations of maternal intake of milk, fish, calcium, n-3 and n-6 fatty acids, trans fatty acids, magnesium, folate, and vitamins C, D, and E from both foods and supplements with development of PE or GH.
Section snippets
Population and Study Design
Study subjects were participants in Project Viva, a prospective observational cohort study of gestational diet and other behaviors, pregnancy outcomes, and offspring health. We recruited women attending their initial prenatal visit at one of eight urban and suburban obstetrical offices in a multispecialty group practice in eastern Massachusetts from 1999 to 2002. Recruitment and retention details have been summarized previously 21, 22. All mothers provided informed consent, and all procedures
Results
Among the 1718 participants in this study, 59 (3%) developed PE, and 119 developed (7%) GH. Half (49%) were nulliparous. Consistent with other studies, women with PE were more likely to be nulliparous, age < 20 or > 40 years, black, unmarried, less educated, overweight, have higher first-trimester systolic blood pressure, and have a prior history or PE or GH (Table 1). Women who developed GH were more likely to be nulliparous, white, less educated, overweight, have a higher first trimester
Discussion
In this prospective study, we found no evidence that intake of calcium, folate, or antioxidant vitamins reduced risk for PE or GH or that intake of n-6 or trans fatty acids increased risks. We observed a somewhat reduced risk for PE associated with intake of elongated n-3 fatty acids and fish. The prevalence of and risk factors for GH and PE in our population were similar to those reported in previous studies (30).
The hypothesis that fish oil might be protective against hypertensive disorders
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2023, Fertility and SterilityPre-pregnancy fat intake in relation to hypertensive disorders of pregnancy
2022, American Journal of Clinical NutritionEarly-pregnancy plasma per- and polyfluoroalkyl substance (PFAS) concentrations and hypertensive disorders of pregnancy in the Project Viva cohort
2022, Environment InternationalCitation Excerpt :FOSA was only detected in 10% of samples and was not included in further analyses. For our primary outcome of hypertensive disorders of pregnancy (HDP), we abstracted clinical data on blood pressure, urine protein, and diagnostic and discharge codes related to gestational hypertension or preeclampsia from medical records as previously described (Oken et al., 2007). We defined gestational hypertension and preeclampsia following the National High Blood Pressure Education Program’s recommendations from the study time period (2000).
Maternal fats and pregnancy complications: Implications for long-term health
2020, Prostaglandins Leukotrienes and Essential Fatty AcidsCitation Excerpt :These studies indicate that an optimal intake of dietary fat is important in preventing preterm births. A higher maternal intake of the omega-3 fatty acids particularly DHA and eicosapentaenoic acid (EPA) is associated with a lower risk of preeclampsia [42]. A recent study in Danish women reported that higher intake of DHA is inversely related to preeclampsia while alpha-linolenic acid (ALA) was found to increase the risk of severe preeclampsia [50].
This project was supported by grants from the National Institutes of Health (HD 34568, HL 64925, HL 68041, HD 44807), the Robert H. Ebert Fellowship, the March of Dimes Birth Defects Foundation, and by Harvard Medical School and the Harvard Pilgrim Health Care Foundation.