Figure 1.

OR and 95% CI of GDM according to supplemental folate intake. The model was estimated using restricted cubic spline logistic regression models with three knots, taking account of age (months), race (white, African American, Hispanic, Asian, others), parity (0, 1, 2, ≥3), family history of diabetes (yes, no), physical activity (quartiles), prepregnancy BMI (<21.0, 21.0‒22.9, 23.0‒24.9, 25.0‒26.9, 27.0‒28.9, 29.0‒30.9, 31.0‒32.9, 33.0‒34.9, ≥35.0 kg/m²), cigarette smoking (never, past, current), alcohol use (0, 0.1‒5.0, 5.1‒9.9, ≥10 g/day), and quartiles of dietary intakes of total energy, glycemic load, saturated fat, total fiber, and heme iron.