Table 2.
Maternal and neonatal characteristics by diabetes type
| Type 1 diabetes n = 1563 (53%)a |
Type 2 diabetes n = 1386 (47%)a |
p value | |
|---|---|---|---|
| Age at delivery (years) | 29.9 (5.7) | 33.6 (5.2) | <0.001 |
| Duration of diabetes (years) | 14.9 (8.3) | 4.8 (4.3) | <0.001 |
| BMI (kg/m2)b | 26.8 (5.6) | 33.3 (7.3) | <0.001 |
| BMI category | |||
| 18.5–24.9 | 660 (42%) | 159 (11%) | |
| 25–29.9 | 473 (30%) | 264 (19%) | |
| ≥ 30 | 335 (21%) | 885 (64%) | |
| Ethnicity | n = 1201 | n = 884 | |
| White | 883 (74%) | 406 (46%) | <0.05 |
| Asian | 27 (2%) | 247 (28%) | |
| Black | 32 (3%) | 79 (9%) | |
| Mixed/other | 43 (4%) | 47 (5%) | |
| Not stated/unknown | 216 (18%) | 105 (12%) | |
| Deprivation quintile | n = 1197 | n = 880 | <0.001 |
| 1: least deprived | 17.5% | 7.4% | |
| 2 | 18.6% | 11.5% | |
| 3 | 21.7% | 17.0% | |
| 4 | 21.3% | 25.6% | |
| 5: most deprived | 20.9% | 38.5% | |
| 5 mg preconception folic acid | 720 (46.1%) | 312 (22.5%) | <0.001 |
| Booking before 8 weeks | 850 (54.4%) | 501 (36.2%) | <0.001 |
| Potentially harmful medications | 45 (2.9%) | 119 (8.6%) | <0.001 |
| Early pregnancy HbA1c | n = 1306 | n = 1024 | |
| % | 7.6 (6.8–8.7) | 6.8 (6.2–8.0) | <0.001 |
| mmol/mol | 60.0 (51.0–72.0) | 51.5 (44.0–64.3) | |
| HbA1c < 6.5% (48 mmol/mol) | 16.2% | 38.3% | |
| Late pregnancy HbA1c | n = 1210 | n = 1017 | |
| % | 6.7 (6.1–7.5) | 5.9 (5.5–6.5) | <0.001 |
| mmol/mol | 50 (43–58) | 41 (37–47) | |
| HbA1c < 6.5% (48 mmol/mol) | 40.0% | 76.0% | |
| Perinatal outcomesc,d | |||
| Gestational age at delivery (weeks) | 36.4 (2.0) | 37.1 (2.0) | <0.001 |
| Preterm delivery <37+0 weeks | 568 (39.7%) | 278 (21.7%) | <0.05 |
| LGA >90th percentile | 667 (46.4%) | 307 (23.9%) | <0.05 |
| LGA >97.7th percentile | 423 (29.4%) | 180 (14.0%) | |
| Serious adverse pregnancy outcomed | |||
| Congenital anomaly | 69 (46.2/1000) | 46 (34.6/1000) | NS |
| Stillbirth | 16 (10.7/1000) | 14 (10.5/1000) | NS |
| Neonatal death | 12 (8.1/1000) | 15 (11.4/1000) | NS |
Data are presented as n (%), mean (SD), median (IQR) or n (n per 1000 births)
a87 (3%) women had ‘other’ types of diabetes, these pregnancies were excluded from analyses comparing type 1 and type 2 diabetes
bThe maternal BMI at booking was unknown for four women with type 1 and two women with type 2 diabetes
cThe gestation age at delivery was available for 1433 infants of mothers with type 1 diabetes and for 1280 with type 2 diabetes. The customised birthweight percentiles were calculated for 1438 infants of mothers with type 1 diabetes and for 1287 with type 2 diabetes
dThe data presented for serious adverse pregnancy outcomes and perinatal complications include only singleton infants