Estimated impact of introduction of new diagnostic criteria for gestational diabetes mellitus

Table 2 Pregnancy outcomes per group based on classification of oral glucose tolerance test results

	n	Group 1: non-GDM	Group 2: GDM by WHO 1999 only1	P value2	Group 3: GDM by WHO 2013 only	P value2	Group 4: GDM by both criteria1	P value2
n (%)	3338	2119 (63.5)	137 (4.1)		576 (17.2)		506 (15.2)
Maternal
Highest diastolic blood pressure, mmHg	3103	75 (70-82)	80 (70-85)	0.060	80 (75-85)	< 0.001	80 (75-85)	< 0.001
Highest diastolic blood pressure, n (%)	3103
< 90 mmHg		1691 (86.1)	111 (84.1)	0.520	429 (81.4)	0.007	379 (79.0)	< 0.001
≥ 90 mmHg		273 (13.9)	21 (15.9)	0.520	98 (18.6)	0.007	101 (21.0)	< 0.001
≥ 110 mmHg		31 (1.6)	3 (2.3)	0.541	4 (0.8)	0.156	7 (1.5)	0.849
Induction of labor, n (%)	3044	335 (17.4)	38 (28.8)	0.001	97 (19.0)	0.390	155 (32.6)	< 0.001
Planned caesarean, n (%)	3044	213 (11.1)	17 (12.9)	0.520	79 (15.5)	0.006	81 (17.1)	< 0.001
Assisted vaginal delivery, n (%)	3059	124 (6.4)	9 (6.8)	0.853	29 (5.6)	0.517	17 (3.6)	0.018
Emergency caesarean, n (%)	3059	223 (11.5)	12 (9.1)	0.394	65 (12.6)	0.492	65 (13.6)	0.205
Blood loss > 1000 cc, n (%)	3019	173 (9.1)	15 (11.4)	0.374	35 (6.9)	0.131	41 (8.7)	0.813
Neonatal
Gestational age at delivery, wk	3070	40.0 (39.0-40.9)	39.4 (38.3-40.6)	0.001	39.9 (38.7-41.0)	0.515	39.1 (38.1-40.0)	< 0.001
Preterm birth, n (%)	3070
Spontaneous		79 (4.1)	7 (5.3)	0.491	26 (5.0)	0.337	33 (6.9)	0.008
Indicated		6 (0.3)	1 (0.8)	0.370	6 (1.2)	0.024	7 (1.5)	0.006
Birth weight, grams	3186	3490 (3090-3840)	3449 (3041-3839)	0.654	3598 (3216-3943)	< 0.001	3420 (2969-3800)	0.056
Birth weight, percentile	3165	50.0 (24.8-75.8)	52.0 (28.8-76.4)	0.388	59.9 (32.6-81.6)	< 0.001	58.7 (29.5-82.1)	< 0.001
Birth weight > 4000 grams, n (%)	3186	325 (16.2)	21 (15.0)	0.719	117 (22.3)	< 0.001	81 (15.9)	0.896
Small-for-gestational-age (< 10th percentile), n (%)	3165	160 (8.0)	6 (4.3)	0.117	28 (5.4)	0.043	34 (6.7)	0.336
Large-for-gestational-age (> 90th percentile), n (%)	3165	203 (10.2)	17 (12.2)	0.435	84 (16.2)	< 0.001	84 (16.6)	< 0.001
Admission to neonatology ward, n (%)	3146	219 (11.0)	15 (10.7)	0.904	59 (11.4)	0.813	103 (20.4)	< 0.001
Admission to NICU, n (%)	3146	75 (3.8)	4 (2.9)	0.576	22 (4.3)	0.620	28 (5.5)	0.077
Shoulder dystocia, n (%)	3173	26 (1.3)	6 (4.3)	0.015	7 (1.3)	0.935	18 (3.5)	0.001
Apgar score 5 min < 7, n (%)	3155	39 (2.0)	4 (2.9)	0.525	20 (3.9)	0.010	24 (4.7)	< 0.001

Continuous variables are presented as mean ± SD or median (interquartile range). Percentages may not add up to 100% due to rounding.

¹Women in this group received treatment for gestational diabetes mellitus.

²P value reported compared to group 1: non-gestational diabetes mellitus.

GDM: Gestational diabetes mellitus; NICU: Neonatal intensive care unit; WHO: World Health Organization.