Whole blood manganese levels in pregnancy and the neonate.

A finding of hypermanganesemia was reported in a pregnant female who received total parenteral nutrition (TPN) for a total of 27 wk as a result of intractable Hyperemesis gravidarum. It was assumed this was the result of the TPN therapy which included manganese (Mn) supplementation. However, the Mn levels continued to rise despite ceasing supplemental Mn, and no evidence of hepatic cholestasis. These high levels were also observed in the 10-d-old neonate, despite a fall in the mother's levels at parturition. A cross sectional study of 19 females at 34 wk pregnancy showed six (31.5%) were outside the quoted reference range for Mn levels. This study was undertaken to monitor Mn levels throughout the pregnancy period and in the neonate in the initial post partum period. Thirty-four pregnant females were randomly recruited from the Gold Coast Hospital antenatal clinic. Whole blood Mn levels were determined for each female on three separate occasions during the trial, at the first visit to the clinic (10-20 wk) and at 25 wk and 34 wk gestation. Mn levels were also determined from blood taken from the baby at neonatal screening (3-4 d old) by heel prick. There was a significant increase in the mean whole blood Mn levels throughout the pregnancy (P<0.0025 and P<0.0005, respectively) and an average three-fold increase in this level in the neonate (P<0.0005). The data confirms a concentrating effect of Mn, as measured by whole blood levels, throughout pregnancy and more dramatically so in the neonate which may indicate a vital role in fetal development.