Table 1.
The characteristics of the women in BiB and UPBEAT
| Characteristic | Born in Bradford, n = 8212 | UPBEAT, n = 859 |
|---|---|---|
| Age, mean (SD) | 27 (5.63) | 30 (5.47) |
| Body mass index, mean (SD) | 26.14 (5.73) | 36.37 (4.98) |
| Smoking in pregnancy, n (%) | 1420 (17.3) | 133 (15.5) |
| Nulliparous, n (%) | 3382 (41.2) | 396 (46.1) |
| Ethnicity, n (%) | ||
| White European | 3629 (44.2) | 573 (66.7) |
| South Asian | 4085 (49.7) | 51 (5.9) |
| Caribbean/African (Black) | 152 (1.9) | 164 (19.1) |
| Others | 346 (4.2) | 71 (8.3) |
| Gestational diabetes WHO, n (%)a | 666 (8.1) | 90 (10.5) |
| Gestational diabetes IADSPG, n (%)b | / | 249 (29) |
| Hypertensive disorder of pregnancy, n (%) | 803 (9.8) | 79 (9.2) |
| Small for gestational age, n (%) | 1139 (13.9) | 59 (6.9) |
| Large for gestational age, n (%) | 617 (7.5) | 102 (11.9) |
| Preterm birth, n (%)c | 430 (5.2) | 39 (4.5) |
| Spontaneous preterm birth, n (%) | 260 (3.2) | 15 (1.6) |
Data are expressed as mean (SD) or n (%) as appropriate. Data were 100% complete. Maternal age and weight/height (used to calculate body mass index (BMI)) were measured at recruitment. Smoking was defined as any smoking during pregnancy. Parity was defined as this pregnancy being their first child (nulliparous) or having previously given birth (multiparous). Ethnicity was based on self-report
aGestational diabetes was diagnosed in the Born in Bradford according to the modified World Health Organization (WHO) criteria operating at the time of the study
bIn UPBEAT, gestational diabetes was defined according to the guidelines recommended by the International Association of Diabetes and Pregnancy Study Groups (IADSPG). We conducted a sensitivity analysis using the WHO criteria in UPBEAT to check the differences were not due to different GDM criteria
cPreterm birth includes spontaneous and iatrogenic preterm birth (birth < 37 weeks gestation)