Obstetric complications and fetal characteristics for type 1 diabetic pregnancies and the background population
| Type 1 diabetic pregnancy | Background population | RR (95% CI) or P | |
|---|---|---|---|
| n | 1,215 | 70,089 | |
| Pre-eclampsia* | 220 (18.1%) | * | <0.001 |
| Caesarean section | 680 (55.9%) | 8,831 (12.6%) | 4.4 (4.1–4.8) |
| Preterm delivery† | 507 (41.7%) | 4,205 (6.0%) | 7.0 (6.3–7.6) |
| Gestational age at delivery (days) | 256 ± 16 | 280 | <0.0001 |
| Birth weight (g) | 3,487 ± 817 | 3,478 | 0.71 |
| Birth weight ≥4,500 g | 97 (8.0%) | 2,383 (3.4%) | 2.3 (1.9–2.9) |
| Large for gestational age infant‡ | 761 (62.5%) | — | <0.001 |
| Stillbirth | 26 (2.1%) | 318 (0.45%) | 4.7 (3.2–7.0) |
| Perinatal mortality | 38 (3.1%) | 525 (0.75%) | 4.1 (2.9–5.6) |
| Congenital malformations | 61 (5.0%) | 1,987 (2.8%) | 1.7 (1.3–2.2) |
| Respiratory distress syndrome§ | 202 (17.1%) | ND | — |
| Jaundice‖ | 215 (18.1%) | ND | — |
Data are means ± SD or n (%).
↵* Blood pressure ≥140/90 mmHg and proteinuria. The frequency in the background population is 2.6% (other data source, see text);
↵† before 37 completed weeks of gestation;
↵‡ birth weight ≥90th centile. The expected frequency in the background population is 10%, but exact numbers are not available;
↵§ use of continuous positive airway pressure for >1 h postpartum;
↵‖ use of phototherapy. ND, no data.