Women’s Health
Maternal magnesium intake and hypertensive disorders of pregnancy among nulliparous women Yijia Zhang* Yijia Zhang Meghan Angley Uma Reddy Ka Kahe
Background and Objectives Magnesium assists muscle relaxation and helps maintain normal blood pressure, and may play a role in the development of hypertensive disorders of pregnancy (HDP). This study examined the associations between magnesium intake, C-reactive protein (CRP), a biomarker for inflammation, and HDP in a large cohort of nulliparous women in the United States.
Methods This study used data from the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-To-Be (NuMoM2b). After excluding women with pre-existing health conditions, i.e., chronic hypertension and pre-gestational diabetes, and women without dietary magnesium data, a total of 7,976 participants were included in the final analysis. Modified Block 2005 Food Frequency Questionnaire was used to assess the intake of magnesium in the three months prior to pregnancy. Women were considered to have HDP if they were diagnosed from 20 weeks’ gestation onwards for new-onset antepartum gestational hypertension, preeclampsia, eclampsia, or superimposed preeclampsia. A subset of the population (n = 2916) had data on serum CRP. We classified CRP levels as either low risk or intermediate-to-high risk for global cardiovascular disease using a cutoff of 1 mg/L. Multivariable logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for the associations between magnesium intake (in quartiles) and the outcomes.
Results The range of magnesium intake (mg/day) for four quartiles were Q1: 4.98–180.02, Q2: 180–241.67, Q3: 241.77–318.27, and Q4: 318.33–1943.27. After adjustment for potential confounders, magnesium intake was associated with lower odds of HDP (Q4 vs. Q1: OR = 0.62, 95% CI = 0.49–0.79; ptrend < 0.001). Higher magnesium intake was also inversely associated with CRP levels (Q4 vs. Q1: OR = 0.61, 95% CI = 0.41–0.90; ptrend = 0.01).
Conclusion Magnesium intake may be associated with a lower risk of HDP, potentially through its anti-inflammatory properties.