Fig. 1

The association of pre-pregnancy BMI and GWG with birth weight. (A) Non-linear associations of pre-pregnancy BMI (kg/m2) with birth weight by the restricted cubic spline regression. (B) Non-linear associations of GWG (kg) with birth weight by the restricted cubic spline regression. Data were both adjusted for maternal age, residence, occupation, education, gravidity, and parity. (C) The mediating effect model of pre-pregnancy BMI, GWG, and birth weight