Early pregnancy maternal trace mineral status and the association with adverse pregnancy outcome in a cohort of Australian women

Maternal micronutrient deficiencies in pregnancy can have profound effects on fetal development and pregnancy outcome. Plasma trace minerals including copper, zinc, selenium and iron have been shown to be extremely important in supporting reproduction. We sought to determine whether there is an association between maternal trace mineral status in early pregnancy and pregnancy complications using a prospective cohort study of 1065 pregnant Australian women who were recruited as part of the Screening for Pregnancy Endpoints (SCOPE) study in Adelaide. Copper, zinc, selenium and iron present in the plasma were measured using mass spectrometry in samples collected at 15 +/- 1 weeks' gestation. After adjusting for covariates, women with lower plasma copper (< 27.9 mu mol/L and 27.9-32.5 mu mol/L) had decreased risk for any pregnancy complication when compared with women with high plasma copper (> 32.5 mu mol/L) (aRR = 0.87; 95% CI = 0.76, 0.99 and aRR = 0.88; 95% CI = 0.78, 1.00, respectively). This was also observed when adjusting for plasma zinc and selenium status ( < 27.9 mu mol/L: aRR = 0.81; 95% CI = 0.69, 0.96 and 27.9-32.5 mu mol/L: aRR = 0.84; 95% CI = 0.72, 0.98). Combined low copper and zinc status was also associated with a reduced risk of any pregnancy complication as compared with high copper and zinc status (aRR = 0.80; 95% CI = 0.70, 0.93). These results provide justification for further work into elucidating the mechanistic role of trace elements in early pregnancy, as well as their interactions in supporting successful pregnancy outcomes.