Changes in blood manganese levels during pregnancy in iron supplemented and non supplemented women.

Blood manganese levels and iron status indices were determined each trimester in 66 healthy pregnant women. Twenty-five were randomly assigned to iron supplementation, 19 to placebo and 22 received dietary advise aimed at increasing their dietary intake of fibre. Iron supplemented women had significantly higher levels of blood haemoglobin compared to the levels of the two other groups, and higher serum ferritin levels compared to the placebo group. No significant difference in blood manganese levels was observed among the three groups of women. There was a significant increase in blood manganese levels from one trimester to the next, which was slightly more pronounced in non supplemented women. The median values in the three trimesters were 154 (range 79-360) nmol/L, 190 (range 98-408) nmol/L, and 230 (range 133-481) nmol/L, respectively. Pregnancy seems to change manganese status or otherwise influence manganese metabolism irrespective of iron status and iron supplementation.