Table 3.

ORs (95% CIs) for pre-eclampsia and GDM by advanced maternal age and pre-pregnancy body mass index

Variables	Pre-eclampsia		GDM
	Model 1	Model 2	Model 1	Model 2
Maternal age (years)
<35	1.00 (Ref)	1.00 (Ref)	1.00 (Ref)	1.00 (Ref)
≥35	1.80 (1.55–2.09)*	1.74 (1.49–2.05)*	1.79 (1.68–1.91)*	1.76 (1.65–1.89)*
Pre-pregnancy BMI
Underweight	0.84 (0.64–1.09)	0.84 (0.64–1.10)	0.63 (0.56–0.70)*	0.62 (0.56–0.70)*
Normal weight	1.00 (Ref)	1.00 (Ref)	1.00 (Ref)	1.00 (Ref)
Overweight/obesity	3.67 (3.15–4.27)*	3.64 (3.12–4.24)*	1.72 (1.59–1.84)*	1.71 (1.60–1.85)*

Underweight (BMI: <18.5 kg/m²), normal weight (BMI: 18.5–23.9 kg/m²), overweight/obesity (BMI: ≥24.0 kg/m²).

Model 1 was adjusted for demographic characteristics including maternal age, residence location, education, nationality, and monthly household income. Model 2 was further adjusted for maternal pre-pregnancy body mass index, drinking in early pregnancy, passive smoking in early pregnancy, smoking in early pregnancy, parity, folic acid supplementation, family history of hypertension, and family history of hyperglycemia. When the variable was the maternal age, model 1 did not adjust for the maternal age; when the variable was the maternal pre-pregnancy BMI, model 2 did not adjust for the maternal pre-pregnancy BMI.

*P<0.001.

BMI, body mass index; GDM, gestational diabetes mellitus.