gms | German Medical Science

Background: During pregnancy, the need for magnesium increases. For low magnesium serum concentrations associations to hypertension, preeclampsia, and gestational diabetes have been shown [1]. Furthermore, oral magnesium is used for pregnancy related symptoms, especially for leg cramps [2], [3]. However, the evidence for therapeutic use of oral magnesium is still not clear and sufficient amounts of magnesium can be absorbed through a diet rich in micronutrients. Therefore, magnesium supplementation during pregnancy is a highly discussed topic in obstetrics and gynaecology.

Materials and methods: To evaluate the magnitude of oral magnesium intake in pregnant women, the data from the LIFE-Child pregnancy cohort were analyzed. The LIFE-Child study (clinical trial number NCT02550236) is a population-based longitudinal cohort study conducted at the Research Center for Civilization Diseases in Leipzig (Saxony, Germany). Records were taken during 24th and 36th week of pregnancy. Those included questionnaires about diseases, medication, and dietary supplement intake. Statistical analyses were done with t-test and chi-square-test as appropriate, using SPSS. In the statistical analysis of each different variable, we included only those questionnaires in which the respondent provided the relevant information. A p-value ≤0.05 was considered to indicate significance.

Results: Magnesium was taken by 48.3% of pregnant women (375/777) in the 24th week and by 51.6% (389/753) in the 36th week. Women taking magnesium had no significant higher serum magnesium concentrations (n=348 [total count of subjects for whom data of magnesium intake and magnesium serum concentration were available], p=0.052, 36th week). No significant correlations between the following diseases of the pregnant women and magnesium intake were found for both record dates: hypertension (24th week: n=497, p=0.507; 36th week: n=470, p=0.298), obesity (24th week: n=512, p=0.464; 36th week: n=485, p=0.28), or diabetes (24th week: n=498, p=0.412; 36th week: n=471, p=0.582). For leg cramp symptoms such as muscle pulling, pricking, tingling or pain (24th week: n=320, p=0.898; 36th week: n=131, p=0.171) and muscle twitching (24th week: n=315, p=0.779; 36th week: n=130, p=0.93) no correlations with magnesium intake were found either. Magnesium intake recorded at 24th and 36th gestation week did not have a beneficial effect on length of gestation (n=490, p=0.681) or birth weight (n=490, p=0.286). The gestational age at birth in women taking magnesium on both or either one of the record dates (n=324) had a mean of 39.79±1.29 weeks of gestation; women who did not take magnesium on both record dates (n=166) had a mean of 39.74±1.24 gestation weeks.

Conclusion: About 50% of pregnant women used magnesium supplements. In this study, no disease-related associations for taking magnesium supplementation were found. The intake of magnesium did not lead to any risks or benefits.