Altered Levels of Serum and Urinary Calcium, Phosphate and Magnesium in Natural Menopausal Versus Surgical Menopausal South Indian Women: A Case Control Study

Background: Women who undergo hysterectomy alone are known to attain menopause 3.7 years earlier than those who attain natural menopause due to altered blood supply to ovaries1. Very few studies are conducted to know the effect of earlier onset of endocrinological changes associated with hysterectomy on the serum and urinary levels of calcium, magnesium and phosphate. Hence the present study was conducted to compare the levels of calcium, magnesium and phosphate in serum and urine of hysterectomised vs. natural postmenopausal women. Methods: The case control study included 26 healthy premenopausal, 22 early surgical menopausal (who were hysterectomised before the age of 50 years) and 21 natural post menopausal women aged above 50 years. Women suffering from endocrine disorders (hypo/hyper parathyroidism, hypo/ hyperpituitarism, ovarian disorders, diabetes), renal failure and malignancy were excluded. Calcium, magnesium and phosphate levels were estimated in serum using calcium-cresoptholone complex, magnesium-calmagite complex and Ammonium phosphomolybdate method respectively. Creatinine was estimated in random urine by kinetic jaffe's method. Calcium/creatinine, magnesium/creatinine and phosphate/creatinine ratio were estimated in random urine using same methods. Estimations were done spectrophotometrically in a fully automated Cobas c311 analyser after appropriate quality control check. Statistical analysis for significance of difference between means was done using ANOVA and kruskal Wallis test by SPSS 13 software. Results: Natural post-menopausal(serum calcium:9.12±0.46 mg/dl; magnesium:2.1±0.23 mg/dl) (urine calcium/creatinine: 0.18±0.13; magnesium/creatinine: 0.09±0.05) and hysterectomised women (serum calcium: 8.83±0.63 mg/dl; magnesium: 2.0±0.16 mg/dl) (urine calcium/creatinine: 0.16±0.1; magnesium/creatinine: 0.07±0.04) have decreased levels of serum calcium and increased serum magnesium, urine calci