Concentrations of essential trace elements in maternal serum and the effect on birth weight and newborn body mass index in sub-arctic and arctic populations of Norway and Russia
Jo. Odland et al., Concentrations of essential trace elements in maternal serum and the effect on birth weight and newborn body mass index in sub-arctic and arctic populations of Norway and Russia, ACT OBST SC, 78(7), 1999, pp. 605-614
Background. This project is part of an assessment of the impact of environm
ental factors on human health in the Kola Peninsula of Russia and the neigh
boring arctic area of Norway. Pregnant women and their newborns were studie
d to explore a relationship between maternal status of essential metals and
birth weight.
Methods. Life-style information and serum specimens were collected from at
least 50 consecutive mother-infant pairs from hospital delivery departments
in three Russian and three Norwegian communities (N=151 and 167, respectiv
ely). Pregnancy outcomes were verified by consulting medical records. Coppe
r, selenium and zinc in serum were determined by atomic absorption spectrom
etry and ferritin by an automated analyzer method.
Results. Mean birth weight and child's body mass index (BMIC) were signific
antly lower in the Russian group (p<0.001), with or without adjustment for
gestational age. Copper, iron (as ferritin) and selenium serum concentratio
ns were in the normal range, while zinc levels in both countries were mostl
y below the lower limit (10.8 mu mol/L) of reported reference intervals. A
positive correlation between zinc and birth weight or BMIC was only observe
d for concentrations exceeding 10.8 mu mol/L. Analysis by quartiles showed
that maternal urinary creatinine and birth weight were negatively correlate
d (p=0.001). The influence of the different elements on BMIC, grouped by qu
artiles, was significantly positive only for selenium (p=0.03) and ferritin
(p=0.02), while there was no significant relationship for copper or zinc.
Adjustment of birth weight and BMIC for gestational age did not alter subst
antially the various associations indicated.
Conclusions. With the exception of zinc, the mineral status of delivering w
omen in arctic and sub-arctic regions of Norway and western Russia appears
to be adequate. The significantly lower BMIC for the Russian group suggests
the likely occurrence of nutritional deficiencies during pregnancy in Russ
ia. However, the significant contribution of a country factor in the predic
tive model implies that the maternal serum trace-element concentrations exp
lored in this study are incomplete indicators of fetal undernourishment.