Figure 2.

Changes in the birth outcomes associated with overall and regional specific blood elements concentrations (A-1,B-1,C,D). The results of logistic regression analyses show the relationships between tertile of maternal elements levels and preterm birth and low birth weight (A-2,B-2). The elements concentrations were natural logarithms transformed. Effect estimates presented as changes in the gestational age, birth weight, length, and head circumference for one ln-unit change in the elements. The odds ratios of the logistic regression analyses are displayed with 95% confidence interval, with the first tertile of the elements levels as the reference. All models were adjusted for maternal age, parity, pre-pregnancy BMI, smoking, and education. In addition, birth weight and birth length were added into the gestational age regression model (A-1), and gestational age was introduced into the birth weight (B-1), length (C), and head circumference (D) regression models. Low birth weight was introduced into preterm birth (A-2) and preterm birth was introduced into low birth weight model (B-2). Abbreviations: As, arsenic; Cd, cadmium; Cu, copper; Hg, mercury; Mn, manganese; Pb, lead; Se, selenium; and Zn, zinc.