| Group 1: Non-GDM based on both 1999 and 2013 WHO criteria (n = 861) | Group 2: Reclassified from GDM to non-GDM using 2013 WHO criteria (n = 89) | Group 3: Reclassified from non-GDM to GDM using 2013 WHO criteria (n = 27) | Group 4: GDM based on both 1999 and 2013 WHO criteria (n = 115) | P value (Group 2 vs. 1) | P value (Group 3 vs. 1) | P value (Group 4 vs. 1) |
---|---|---|---|---|---|---|---|
Characteristics | |||||||
 Age, years [mean (SD)] | 30.2 (5.1) | 32.2 (4.9) | 31.2 (5.4) | 32.7 (4.6) | 0.001 | 0.348 | < 0.001 |
 Body mass index, kgm−2 [mean (SD)] | 23.3 (4.6) | 24.0 (4.5) | 28.0 (5.7) | 25.5 (4.9) | 0.195 | < 0.001 | < 0.001 |
 Gestational weight gain, z-score [mean (SD)] | −0.8 (1.1) | −0.8 (0.9) | −0.9 (1.2) | −1.1 (1.1) | 0.581 | 0.792 | 0.024 |
Education, n (%) | |||||||
 None/ primary/ secondary | 573 (67.5) | 48 (53.9) | 20 (80.0) | 70 (60.9) | 0.010 | 0.187 | 0.157 |
 Tertiary | 276 (32.5) | 41 (46.1) | 5 (20.0) | 45 (39.1) |  |  |  |
 Multiparous, n (%) | 450 (52.9) | 46 (51.7) | 20 (74.1) | 70 (60.9) | 0.821 | 0.030 | 0.109 |
 Positive family history of diabetes, n (%) | 242 (28.1) | 28 (31.5) | 16 (59.3) | 39 (33.9) | 0.504 | < 0.001 | 0.197 |
 Smoking during pregnancy, n (%) | 23 (2.7) | 2 (2.3) | 1 (3.8) | 1 (0.9) | > 0.950 | 0.517 | 0.346 |
Type of conception, n (%) | |||||||
 Natural | 810 (94.1) | 83 (93.3) | 25 (92.6) | 98 (85.2) | 0.757 | 0.673 | < 0.001 |
 in vitro fertilization | 51 (5.9) | 6 (6.7) | 2 (7.4) | 17 (14.8) |  |  |  |
Maternal Outcomes | |||||||
 Insulin requirement, n (%) | 0 | 5 (5.6) | 0 | 12 (10.4) | < 0.001 | – | < 0.001 |
 Induction of labour, n (%) | 260 (34.9) | 36 (50.0) | 9 (42.9) | 51 (51.5) | 0.011 | 0.448 | 0.001 |
 Caesarean section, n (%) | 242 (30.1) | 32 (40.0) | 11 (40.7) | 34 (30.6) | 0.069 | 0.239 | 0.915 |
 Instrumental delivery, n (%) | 48 (7.9) | 9 (15.8) | 0 | 4 (4.9) | 0.049 | 0.626 | 0.346 |
 Hypertension and/ or preeclampsia, n (%) | 57 (6.6) | 5 (5.6) | 3 (11.1) | 16 (13.9) | 0.716 | 0.420 | 0.005 |
Neonatal Outcomes | |||||||
 Gestation at birth, weeks [mean (SD)] | 38.4 (1.4) | 38.2 (1.4) | 38.1 (1.3) | 37.9 (2.2) | 0.078 | 0.200 | 0.008 |
 Prematurity, n (%) | 52 (6.1) | 11 (12.4) | 2 (7.4) | 13 (11.3) | 0.025 | 0.680 | 0.038 |
 Apgar score at 1 min [mean (SD)] | 8.9 (0.6) | 8.8 (0.6) | 8.6 (1.6) | 8.8 (0.8) | 0.297 | 0.379 | 0.179 |
 Apgar score at 5 min [mean (SD)] | 9.0 (0.1) | 9.0 (0.1) | 8.9 (0.6) | 9.0 (0.3) | 0.456 | 0.369 | 0.569 |
 Birth weight-for-gestational age, z-score [mean (SD)] | 0.1 (1.1) | 0.1 (1.1) | 0.7 (1.2) | 0.5 (1.6) | 0.861 | 0.006 | 0.012 |
 Small for gestational age, n (%) | 91 (10.7) | 10 (11.2) | 1 (3.7) | 11 (9.6) | 0.881 | 0.348 | 0.706 |
 Large for gestational age, n (%) | 124 (14.6) | 14 (15.7) | 6 (22.2) | 25 (21.7) | 0.776 | 0.271 | 0.047 |
 Macrosomia, n (%) | 15 (1.8) | 1 (1.1) | 1 (3.7) | 2 (1.7) | > 0.950 | 0.397 | > 0.950 |
 Shoulder dystocia, n (%) | 1 (0.1) | 2 (2.4) | 0 | 0 | 0.025 | > 0.950 | > 0.950 |
 Hypoglycaemia, n (%) | 15 (1.9) | 6 (7.3) | 1 (3.8) | 18 (16.2) | 0.011 | 0.413 | < 0.001 |
 Neonatal jaundice requiring phototherapy, n (%) | 86 (11.2) | 17 (20.2) | 7 (26.9) | 22 (20.2) | 0.015 | 0.024 | 0.007 |
 Neonatal intensive care unit admission, n (%) | 30 (3.6) | 5 (5.7) | 2 (7.7) | 6 (5.2) | 0.368 | 0.247 | 0.427 |