Table 2

Pregnancy outcomes stratified according to HbA1c measurement at ≤20 weeks’ (140 days’) gestation, excluding women treated for GDM

HbA1c 5.9–6.4%
(41–46 mmol/mol)
n = 200
n (%)HbA1c <5.9%
(<41 mmol/mol)
n = 7,987
n (%)RR (95% CI)
Delivery gestation
 <37 weeks16 (8.0)392 (4.9)1.66 (1.01–2.74)*
 <32 weeks3 (1.5)71 (0.9)1.67 (0.55–5.10)
Induction of labor35 (17.5)1,016 (12.7)1.44 (1.01–2.06)*
Caesarean delivery
 Total65 (32.5)2,428 (30.4)1.10 (0.82–1.47)
 Emergency33 (16.5)1,529 (19.1)0.84 (0.58–1.21)
Major congenital anomaliesn = 7,992
7 (3.5)103 (1.3)2.67 (1.28–5.53)*
Preeclampsia11 (5.5)181 (2.3)2.42 (1.34–4.38)*
Perinatal death4 (2.0)38 (0.5)3.96 (1.54–10.16)*
Shoulder dystocia5 (2.5)79 (1.0)2.47 (1.05–5.85)*
Birth weightn = 199
 Mean (SD)3,480.2 (597.0)3,483.8 (571.0)P = 0.93
 >4,000 g34 (17.1)1,240 (15.5)1.12 (0.78–1.61)
 Population birth weight centilesn = 199
  Small for gestational age22 (11.1)1,202 (15.1)0.71 (0.46–1.10)
  Large for gestational age26 (13.1)655 (8.2)1.66 (1.11–2.48)*
 Customized birth weight centilesn = 199
  Small for gestational age23 (11.6)1,173 (14.7)0.76 (0.50–1.17)
  Large for gestational age21 (10.1)641 (8.0)1.34 (0.86–2.09)
  • Small for gestational age <10th centile; large for gestational age >90th centile.

  • *Significant difference.

  • †Adjusted for gestational age at delivery and sex of baby.

  • ‡Adjusted for ethnicity, maternal height and weight, parity, gestational age at delivery, and sex of baby. Missing height or weight data defaulted to the population median of 165 cm and 65 kg, respectively.