Calcium and magnesium concentration of breast milk in relation with age and parity of nursing women

The aim of this study was determination of the concentration of calcium and magnesium in human milk (n=150) taken from nursing women who lived permanently in Malopolska district (South Poland). Milk samples were classified into groups taking into account women' age and parity. According to the various age of the women milk samples were segregated into three groups: 20-25 years old, 26-31 years old and 32-37 years old. Included parity milk samples were spitted into two groups: the first group consisted of women who were primiparous (1 baby), the second group included women who were multiparous (less or 2 babies). Milk samples were taken between the 7th and 14th day of the postpartum in each age group. The samples were taken by manual expression every morning. The analyses of metals were done by flame atomic absorption spectrophotometry (FAAS), after all samples had been collected. The mean concentration of cooper in milk taken from women of first age group (20-25 years old) was 209.44 plus minus 15.10 mg per L, in second group (26-31 years old) was 238.65 plus minus 13.34 mg per L and in the oldest group (32-37 years old) was 261.44 plus minus 17.16 mg per L. The mean concentration of magnesium in the same group of age was 42.12 plus minus 3.793 mg per L, 47.51 plus minus 2.728 mg per L and 45.43 plus minus 3.840 mg per L, respectively. The mean concentration of calcium in milk taken from primiparous was 223.17 plus minus 10.50mg per L, in multiparous was 266.37 plus minus 16.20 mg per L. Whereas, the mean concentration of magnesium in transitional milk taken from the same group was 44.12 plus minus 2.58 mg per L and 47.412 plus minus 3.16 mg per L, respectively. Statistical analyses showed that there were statistically significant differences between calcium level in milk taken from the youngest group and the concentration of this metal in milk from the oldest group (p=0.032). Also, when comparing women's parity, significant differences were found in the concentration of calcium (p=0.022). However, the differences in magnesium levels between tested groups were no statistically significant. Additionally, r Pearson correlation coefficient showed positive correlation between analyzed metals (Mg per Ca: r2=0.589; p=0.000). These observations suggest that mothers age and parity have influence on calcium concentration in milk but did not impact on magnesium level in breast milk.