Table 4 The effects of iodine intake and other covariates on natural logarithm of placental weight in univariate and multivariate models
From: Estimated dietary iodine intake as a predictor of placental size: evidence from the ELSPAC study
Univariate models | Multivariate model | |||||
|---|---|---|---|---|---|---|
β estimate | 95% CI for β estimate | p-value | β estimate | 95% CI for β estimate | p-value | |
Iodine intake [100 μg/day] | −0.032 | (−0.050; −0.013) | <0.001 | −0.025 | (−0.044; −0.006) | 0.011 |
Gestational diabetes | ||||||
No | (ref) | (ref) | ||||
Yes | −0.088 | (−0.149; −0.027) | 0.005 | −0.080 | (−0.140; −0.020) | 0.009 |
Pre-eclampsia | ||||||
No | (ref) | (ref) | ||||
Yes | −0.105 | (−0.208; −0.002) | 0.046 | −0.133 | (−0.234; −0.031) | 0.011 |
Gestational hypertension | ||||||
No | (ref) | (ref) | ||||
Yes | 0.062 | (0.010; 0.113) | 0.019 | 0.053 | (0.001; 0.104) | 0.046 |
Gestational age [w] | 0.015 | (0.010; 0.019) | <0.001 | 0.013 | (0.009; 0.018) | <0.001 |
Stillborn | ||||||
No | (ref) | (ref) | ||||
Yes | −0.064 | (−0.149; 0.022) | 0.143 | −0.056 | (−0.140; 0.028) | 0.193 |
IVF pregnancy | ||||||
No | (ref) | (ref) | ||||
Yes | 0.131 | (0.041; 0.220) | 0.004 | 0.141 | (0.051; 0.230) | 0.002 |
Congenital malformations | ||||||
No | (ref) | (ref) | ||||
Yes | 0.016 | (−0.025; 0.057) | 0.453 | 0.016 | (−0.025; 0.056) | 0.443 |
Smoking | ||||||
Never | (ref) | (ref) | ||||
Past smoker | 0.012 | (−0.005; 0.029) | 0.152 | 0.008 | (−0.009; 0.025) | 0.353 |
Current smoker | −0.024 | (−0.052; 0.005) | 0.100 | −0.019 | (−0.049; 0.011) | 0.206 |
Substance abuse | ||||||
No | (ref) | (ref) | ||||
Yes | −0.050 | (−0.134; 0.034) | 0.239 | −0.033 | (−0.116; 0.051) | 0.443 |
Alcohol | ||||||
No | (ref) | (ref) | ||||
Yes | −0.018 | (−0.048; 0.013) | 0.261 | −0.020 | (−0.050; 0.011) | 0.213 |
Nutritional supplements | ||||||
No | (ref) | (ref) | ||||
Yes | 0.050 | (0.035; 0.066) | <0.001 | 0.047 | (0.031; 0.063) | <0.001 |
ISCO skill level - mother | ||||||
Skill level 1 | (ref) | (ref) | ||||
Skill level 2 | 0.005 | (−0.031; 0.040) | 0.805 | 0.001 | (−0.036; 0.037) | 0.978 |
Skill level 3 | −0.009 | (−0.048; 0.030) | 0.639 | −0.015 | (−0.056; 0.027) | 0.493 |
Skill level 4 | −0.006 | (−0.043; 0.031) | 0.741 | −0.014 | (−0.055; 0.027) | 0.506 |
Skill level unassigned | −0.051 | (−0.176; 0.075) | 0.428 | −0.056 | (−0.179; 0.068) | 0.377 |
ISCO skill level - father | ||||||
Skill level 1 | (ref) | (ref) | ||||
Skill level 2 | −0.006 | (−0.059; 0.046) | 0.814 | −0.007 | (−0.059; 0.044) | 0.783 |
Skill level 3 | −0.026 | (−0.083; 0.031) | 0.369 | −0.019 | (−0.076; 0.038) | 0.508 |
Skill level 4 | −0.013 | (−0.066; 0.041) | 0.641 | 0.010 | (−0.046; 0.065) | 0.734 |
Skill level unassigned | 0.004 | (−0.056; 0.064) | 0.894 | 0.026 | (−0.033; 0.085) | 0.386 |
Education – mother | ||||||
Basic | (ref) | (ref) | ||||
Secondary | 0.005 | (−0.012; 0.023) | 0.529 | 0.022 | (0.002; 0.043) | 0.035 |
University and higher | 0.000 | (−0.021; 0.022) | 0.977 | 0.033 | (0.001; 0.065) | 0.043 |
Education – father | ||||||
Basic | (ref) | (ref) | ||||
Secondary | −0.001 | (−0.021; 0.018) | 0.880 | −0.001 | (−0.023; 0.021) | 0.936 |
University and higher | −0.016 | (−0.035; 0.003) | 0.090 | −0.025 | (−0.054; 0.004) | 0.091 |
Equalized family intake [1000 CZK/month] | −0.002 | (−0.011; 0.008) | 0.698 | −0.002 | (−0.012; 0.009) | 0.732 |
Age - mother [y] | 0.001 | (−0.001; 0.002) | 0.377 | 0.000 | (−0.001; 0.002) | 0.669 |
Height - mother [cm] | 0.002 | (0.000; 0.003) | 0.012 | 0.002 | (0.000; 0.003) | 0.014 |
Height - father [cm] | 0.000 | (−0.001; 0.001) | 0.973 | 0.000 | (−0.002; 0.001) | 0.501 |
Maternal preconceptional BMI [kg/m2] | 0.008 | (0.006; 0.010) | <0.001 | 0.007 | (0.005; 0.010) | <0.001 |
Ethnicity – mother | ||||||
European | (ref) | (ref) | ||||
Others | −0.029 | (−0.100; 0.042) | 0.429 | 0.020 | (−0.063; 0.104) | 0.632 |
Ethnicity – father | ||||||
European | (ref) | (ref) | ||||
Others | −0.039 | (−0.094; 0.016) | 0.168 | −0.018 | (−0.083; 0.047) | 0.591 |
Sex of the child | ||||||
Girl | (ref) | (ref) | ||||
Boy | 0.029 | (0.014; 0.045) | <0.001 | 0.029 | (0.014; 0.045) | <0.001 |