Table 2.
Characteristics of women included in each dataset
| Study characteristics | Older CUHFT cohort | Recent CUHFT cohort | OPHELIA cohort |
|---|---|---|---|
| n = 17736 | n = 826 | n = 361 | |
| Time period covered | 2004–2008 | 2014–2019 | Oct 2019–ongoing |
| Study design | Retrospective service evaluation | Retrospective service evaluation | Prospective observational study |
| Population | All singleton pregnancies with liveborn infants | All singleton pregnancies with GDM diagnosed according to IADPSG criteria | Singleton pregnancies with ≥1 positive NICE risk factor |
| Centres | Single centre | Single centre | Four East of England centres |
| Who had a random plasma glucose at 12 weeks? | All women offered, results available in 72%† | Not applicable | Not applicable |
| Who had a 75‐g OGTT at 24–28 weeks? | Women with a 24‐week 50‐g glucose challenge result >7.7 mmol/l | Women with ≥1 GDM risk factor | Women with ≥1 GDM risk factor |
| GDM diagnostic criteria | 1998 WHO [31] | IADPSG [2] | NICE [3] |
| Treatment offered, n/N (%) | 776/17736 (4.4) | 826/826 (100) | 30/331 (8.3) |
| Maternal characteristics | |||
| Mean (sd) maternal age years | 30.9 (5.6) | 33.6 (5.4) | 31.7 (4.9) |
| Mean (sd) pre‐pregnancy BMI, kg/m2 | 24.8 (5.0) | 29.4 (7.5) | 33.0 (6.7) |
| Primiparous, n (%) | 9895 (56) | 283 (34) | 132 (37) |
| Ethnicity, n (%) | n=670 | n=345 | |
| White | 15934 (90) | 531 (79) | 315 (91) |
| Black | 258 (1.5) | 14 (2.1) | 29 (8.4) |
| Asian | 899 (5.1) | 111 (17) | 1 (0.3) |
| Other | 644 (3.6) | 14 (2.1) | 0 (0.0) |
| Maternal smoking, n (%) | 1643 (9.3) | 61/747 (8.2) | N/A |
| Mean (sd) random plasma glucose mmol/l at 12 weeks, mmol/l | 5.8 (1.4) | N/A | N/A |
| Mean (sd) HbA1c at 28 weeks, mmol/mol | N/A | 35.9 (4.9) | 32.5 (3.6) |
|
OGTT at 28 weeks |
n = 3848 |
n = 821–824 |
n = 359–360 |
| Mean (sd) Fasting glucose (OGTT time 0) | 4.5 (0.6) | 4.9 (0.7) | 4.4 (0.5) |
| Mean (sd) OGTT time 60 mins | 8.5 (1.9) | 10.6 (1.5) | N/A |
| Mean (sd) OGTT time 120 mins | 6.9 (1.6) | 7.6 (1.4) | 5.8 (1.4) |
|
Pregnancy outcomes |
n = 17001–17736 |
n = 817‐826 |
n = 278 |
| Mean (sd) estimated gestational age at birth, weeks | 39.2 (2.0) | 38.5 (1.4) | 39.4 (1.5) |
| LGA infant, n (%) | 2112 (1) | 134 (16) | N/A |
| Caesarean section, n (%) | 5005 (28) | 342 (41) | N/A |
| Neonatal hypoglycaemia, n (%) | N/A | 386 (47) | N/A |
| NICU admission, n (%) | 1071 (6.1) | 124 (15) | N/A |
CUHFT, Cambridge University Hospital NHS Foundation Trust; FPG, fasting plasma glucose; LGA, large‐for‐gestational‐age; NICU, neonatal intensive care unit.
Neonatal hypoglycaemia defined as neonatal glucose <2.6 mmol/l at least 4 h after birth. NICU admission defined as >24 h.
†
No difference between women with and without a random plasma glucose. 31