a positive trendp = 0.182
Multivariate regression analyses ( Table 5 ) showed a positive trend between maternal hair Hg and birth weight (β coefficient = 154.6; 95% CI = −73.29–382.5; standard error = 115.0; p = 0.182), and an opposite effect on birth length (β coefficient = −0.089; 95% CI = −1.518–1.340; standard error = 0.721; p = 0.902), after adjusting the effects of babies’ gender, gestational age, and maternal BMI before pregnancy and education, but the association was not statistically significant. 4.