Association of Gestational Diabetes Mellitus with Adverse Pregnancy Outcomes and Its Interaction with Maternal Age in Chinese Urban Women

Table 3

ORs (95% CIs) for pregnancy outcomes by gestational diabetes mellitus, stratified by maternal age.

	years		years		for interaction
	OR (95% CI)	value	OR (95% CI)	value
Cesarean delivery
Model 1	1.75 (1.53, 2.01)	<0.001	1.27 (0.84, 1.91)	0.255	0.042
Model 2	1.71 (1.49, 1.97)	<0.001	1.13 (0.74, 1.73)	0.559	0.025
Preterm birth
Model 1	1.49 (1.19, 1.88)	<0.001	0.75 (0.40, 1.41)	0.376	0.158
Model 2	1.45 (1.15, 1.83)	0.002	0.73 (0.38, 1.40)	0.334	0.133
Low birth weight
Model 1	1.25 (0.92, 1.69)	0.155	0.83 (0.37, 1.89)	0.665	0.539
Model 2	0.81 (0.54, 1.22)	0.319	2.28 (0.55, 9.43)	0.256	0.383
SGA
Model 1	0.81 (0.60, 1.10)	0.176	0.63 (0.26, 1.51)	0.298	0.532
Model 2	0.80 (0.59, 1.08)	0.143	0.63 (0.25, 1.58)	0.322	0.463
Macrosomia
Model 1	1.49 (1.18, 1.90)	0.001	1.58 (0.81, 3.08)	0.178	0.830
Model 2	1.65 (1.28, 2.11)	<0.001	1.52 (0.73, 3.16)	0.265	0.954
LGA
Model 1	1.43 (1.17, 1.75)	<0.001	1.55 (0.89, 2.72)	0.121	0.963
Model 2	1.39 (1.13, 1.70)	<0.001	1.35 (0.75, 2.44)	0.316	0.898

Abbreviations: CI: confidence interval; OR: odds ratio; SGA: small for gestational age; LGA: large for gestational age. Model 1 was adjusted for demographic characteristics including maternal age, education, employment, annual household income, and study centers. Model 2 was further adjusted for drinking during pregnancy, passive smoking during pregnancy, prepregnancy body mass index categories, parity, use of assisted reproductive technology, folic acid supplementation, gestational age at delivery, and gestational weight gain categories. Preterm birth was not adjusted for gestational age at delivery.