Table 3.
Pregnancy outcomes according to the GDM classification groups
| NGT | WHO 1999 | WHO 2013 | WHO 2013 fasting glucose only | WHO 1999 2HG only | |||
|---|---|---|---|---|---|---|---|
| Pregnancy outcomes | General obstetric population in the north of the Netherlands | Criteria (mmol/l) | Fasting glucose <5.1 and 2HG <7.8 | Fasting glucose ≥7.0 and/or 2HG ≥7.8 | Fasting glucose ≥5.1 and/or 2HG ≥8.5 | Fasting glucose ≥5.1- ≤ 6.9 and 2HG <7.8 | Fasting glucose <5.1 and 2HG ≥7.8- ≤ 8.4 |
| N b | |||||||
| N | 29,562 | 4431 | 2851 | 913 | 1346 | 667 | 234 |
| Treated for GDM, n | 0 | 913 | 679 | 0 | 234 | ||
| Maternal | |||||||
| Gestational hypertension, n (%) | 4427 | 139 (4.9) | 62 (6.8)* | 98 (7.3)** | 52 (7.8)** | 16 (6.9) | |
| Preeclampsia, n (%) | 4427 | 41 (1.4) | 28 (3.1)** | 35 (2.6)** | 12 (1.8) | 5 (2.1) | |
| Induction of labour, n (%) | 4405 | 793 (28.0) | 587 (64.3)*** | 670 (50.0)*** | 230 (34.8)** | 147 (62.8)*** | |
| Mode of delivery, n (%) | 4410 | ||||||
| Vaginal | 2051 (72.3) | 618 (67.7)** | 904 (67.4)** | 451 (68.1)* | 165 (70.5) | ||
| Emergency CS | 327 (11.5) | 116 (12.7) | 177 (13.2) | 89 (13.4) | 28 (12.0) | ||
| Planned CS | 185 (6.5) | 103 (11.3)*** | 150 (11.2)*** | 68 (10.3)** | 21 (9.0) | ||
| Instrumental | 272 (9.6) | 76 (8.3) | 110 (8.2) | 54 (8.2) | 20 (8.5) | ||
| Gestational age at delivery (weeks) | 4431 | 39.7 (38.7–40.6) | 38.3 (38.0–39.0)*** | 38.7 (38.0–39.9)*** | 39.6 (38.3–40.4)*** | 38.6 (38.1–39.4)*** | |
| Neonatal | |||||||
| LGA, n (%) | 3246 (11.0) | 4430 | 514 (18.0) | 167 (18.3) | 271 (20.1) | 140 (21.0) | 36 (15.4) |
| Macrosomia, n (%) | 4275 (14.5) | 4431 | 595 (20.9) | 108 (11.8)*** | 226 (16.8)** | 148 (22.2) | 30 (12.8)** |
| Small for gestational age, n (%) | 2364 (8.0) | 4430 | 195 (6.8) | 36 (3.9)** | 69 (5.1)* | 38 (5.7) | 5 (2.1)** |
| Birthweight (g) | 4431 | 3544 ± 579 | 3391 ± 550*** | 3477 ± 590** | 3580 ± 596 | 3437 ± 498** | |
| Birth trauma, n (%) | 4420 | 64 (2.3) | 27 (3.0) | 43 (3.2) | 20 (3.0) | 4 (1.7) | |
| Hypoglycaemia, n (%)a | 4418 | NA | 38 (4.2)*** | NA | NA | 4 (1.7) | |
| Hyperbilirubinaemia, n (%)a | 4418 | NA | 24 (2.6)** | NA | NA | 5 (2.1) | |
| Stillbirth, n (%) | 4431 | 10 (0.4) | 2 (0.2) | 6 (0.4) | 4 (0.6) | 0 | |
| Preterm delivery, n (%) | 4431 | 146 (5.1) | 57 (6.2) | 92 (6.8)* | 46 (6.9) | 11 (4.7) | |
| Respiratory support, n (%) | 4418 | 116 (4.1) | 34 (3.7) | 51 (3.8) | 27 (4.1) | 10 (4.3) | |
| Apgar score <7 at 5 min, n (%) | 4414 | 74 (2.6) | 30 (3.3) | 57 (4.3)** | 29 (4.4)* | 2 (0.9) | |
| Admission to neonatology, n (%) | 4423 | 315 (11.1) | 130 (14.2)* | 206 (15.3)*** | 100 (15.0)** | 24 (10.3) |
Data are expressed as mean ± SD, median (IQR) or proportion of n (%)
aData were collected in primary care (midwives) and secondary care (hospital). In primary care, neonatal hypoglycaemia and hyperbilirubinaemia were not reported and measured in all pregnancies. Therefore we only report the percentages for the WHO 1999 group, as all these women delivered in secondary careb Data with respect to gestational hypertension, preeclampsia, induction of labour, mode of delivery, birth trauma, hypoglycaemia, hyperbilirubinaemia, respiratory support, Apgar score and admission to the neonatology are missing in 4 (0.09%), 4 (0.09%), 26 (0.5%), 21 (0.5%), 11 (0.2%), 13 (0.3%), 13 (0.3%), 13 (0.3%), 17 (0.4%) and 8 (0.2%) of the subjects, respectively
p values are based on Student’s unpaired t test (non-skewed continuous variables), Mann–Whitney U test (skewed continuous variables), or χ 2 test/Fisher’s exact test. *p<0.05, **p<0.01, ***p<0.001 compared with NGT group