Comparison of magnesium status using 24-hour urine magnesium content and magnesium fraction excretion in PCOS with non-PCOS control women: A cross-sectional study

Abstract Objective. Magnesium (Mg) is the second most frequent intracellular cation, have an important role in normal enzyme function and insulin secretion. Polycystic Ovarian Syndrome (PCOS) is the most prevalent endocrinopathy in women of reproductive age and often associated with insulin resistance. Two systematic reviews and meta-analyses have been conducted to compare mean serum Mg levels between PCOS and control groups. Both studies detected unexplained heterogeneity among input studies and the two conclusions contradict each other; while approximately 1% of total body Mg is present in Extracellular Fluid (ECF) and serum Mg level does not represent Mg status well. For the first time, we investigated Magnesium renal Fraction Excretion (FEMg) and compared mean values between PCOS and non-PCOS control women. Design.Cross-sectional analysis. Setting. Academic medical center. Population. 44 women were included in PCOS group based on Rotherdam criteria and 50 non-PCOS women in control group. Method. Statistical analysis of the relationship between 24-hour urinary Mg content, FEMg, and also physical and metabolic variables. The STROBE guidelines for cross-sectional study was followed. Main outcome measurements. 24-hour urinary Mg content, FEMg. Results.Mean values of 24-hour urinary Mg content and FEMg did not significantly differ between PCOS and control groups (P=0.22 and P=0.24, respectively). Also serum Mg levels were similar between the groups (P=0.17). Conclusion. Our data did not suggest Mg play a role in PCOS pathogenesis. For further investigation, we recommend using FEMg for evaluating Mg status rather than serum Mg levels.