Table 3 Association between maternal metal concentrations and GDM

Cu (µmol/L)

1.23

1.03, 1.47

0.026

1.26

1.04, 1.52

0.018

1.23

1.02, 1.49

0.031

 1st tertile (≤ 14.59)

Ref

Ref

Ref

 2nd tertile (14.60 ~ 18.95)

1.06

0.92, 1.21

0.443

1.07

0.93, 1.23

0.342

1.08

0.92, 1.27

0.328

 3rd tertile (≥ 18.96)

1.13

0.99, 1.30

0.068

1.15

1.00, 1.33

0.050

1.18

1.01, 1.39

0.042

Zn (µmol/L)

1.53

1.04, 2.24

0.029

1.57

0.93, 2.66

0.093

1.46

0.86, 2.48

0.159

 1st tertile (≤ 79.17)

Ref

Ref

Ref

 2nd tertile (79.18 ~ 89.99)

1.05

0.92, 1.21

0.474

1.06

0.91, 1.21

0.525

1.03

0.89, 1.19

0.687

 3rd tertile (≥ 90.00)

1.16

1.01, 1.32

0.035

1.14

0.97, 1.35

0.120

1.11

0.93, 1.31

0.244

Ca (mmol/L)

0.49

0.28, 0.86

0.013

0.25

0.13, 0.47

< 0.001

0.36

0.19, 0.69

0.002

 1st tertile (≤ 1.50)

Ref

Ref

Ref

 2nd tertile (1.51 ~ 1.65)

0.83

0.73, 0.95

0.009

0.79

0.68, 0.91

< 0.001

0.82

0.71, 0.95

0.006

 3rd tertile (≥ 1.66)

0.88

0.77, 1.00

0.051

0.78

0.67, 0.90

0.001

0.84

0.73, 0.97

0.022

Mg (mmol/L)

1.56

0.85, 2.86

0.153

1.27

0.54, 2.96

0.587

0.86

0.37, 2.00

0.719

 1st tertile (≤ 1.34)

Ref

Ref

Ref

 2nd tertile (1.35 ~ 1.44)

1.07

0.93, 1.23

0.327

1.05

0.92, 1.21

0.467

1.04

0.90, 1.20

0.573

 3rd tertile (≥ 1.45)

1.08

0.94, 1.23

0.286

1.00

0.84, 1.19

0.969

0.93

0.78, 1.11

0.425

Fe (mmol/L)

1.72

1.03, 2.90

0.040

1.38

0.63, 3.02

0.420

1.44

0.66, 3.17

0.361

 1st tertile (≤ 7.38)

Ref

Ref

Ref

 2nd tertile (7.39 ~ 7.98)

1.05

0.91, 1.20

0.510

1.04

0.90, 1.20

0.616

1.04

0.90, 1.21

0.562

 3rd tertile (≥ 7.99)

1.15

1.01, 1.21

0.037

1.15

0.96, 1.38

0.140

1.15

0.96, 1.38

0.130