Table 1 Characteristics of the singleton cohort by ethnicity and gestational diabetes status
| Â | White European | South Asian | ||||
|---|---|---|---|---|---|---|
All (N = 4747) | No GDM (N = 4537) | GDM (N = 210) | All (N = 5958) | No GDM (N = 5336) | GDM (N = 622) | |
Infant characteristics | ||||||
 Sex, % (N) | ||||||
  Male | 51.7 (2455) | 51.8 (2351) | 49.5 (104) | 51.5 (3069) | 51.4 (2743) | 52.4 (326) |
  Female | 48.3 (2292) | 48.2 (2186) | 50.5 (106) | 48.5 (2889) | 48.6 (2593) | 47.6 (296) |
 Ethnicity by country, % (N) | ||||||
  White British | 92.6 (4396) | 92.7 (4204) | 91.4 (192) | – | – | – |
  White other | 7.4 (351) | 7.3 (333) | 8.6 (18) | – | – | – |
  Pakistani | – | – | – | 87.0 (5181) | 87.1 (4649) | 85.5 (532) |
  Indian | – | – | – | 7.2 (43) | 7.4 (392) | 6.4 (40) |
  Bangladeshi | – | – | – | 5.8 (345) | 5.5 (295) | 8.0 (50) |
Birthweight (g), mean (SD) | 3354 (550) | 3359 (551) | 3246 (450) | 3140 (515) | 3145 (517) | 3094 (489) |
 Missing, % (N) | 0.2 (8) | 0.2 (8) | 0 (0) | 0.03 (2) | 0.04 (2) | 0 (0) |
Gestational age at birth (years), mean (SD) | 39.3 (1.8) | 39.4 (1.8) | 38.1 (1.5) | 39.1 (1.7) | 39.2 (1.7) | 38.2 (1.3) |
 Missing, % (N) | 0.2 (8) | 0.2 (8) | 0 (0) | 0.03 (2) | 0.04 (2) | 0 (0) |
 Intergrowth birth weight centiles (full cohort analyses), % (N)* | ||||||
  SGA (< 10th) | 8.0 (377) | 8.1 (368) | 4.3 (9) | 16.2 (962) | 16.7 (891) | 11.4 (71) |
  LGA (> 90th) | 14.9 (707) | 14.8 (669) | 18.1 (38) | 7.0 (419) | 6.6 (354) | 10.5 (65) |
  Missing | 0.2 (8) | 0.2 (8) | 0 (0) | 0.03 (2) | 0.04 (2) | 0 (0) |
 Intergrowth birth weight centiles (restricted analyses), % (N)* | ||||||
  SGA (< 10th) | 7.1 (275) | 7.3 (268) | 3.6 (7) | 16.4 (730) | 17.0 (677) | 11.3 (53) |
  LGA (> 90th) | 15.1 (584) | 15.0 (552) | 16.8 (32) | 6.7 (297) | 6.2 (246) | 10.8 (51) |
  Missing | 18.6 (884) | 19.0 (864) | 9.5 (20) | 25.3 (1508) | 25.4 (1357) | 24.3 (151) |
 Customized birth weight centiles, % (N)** | ||||||
  SGA (< 10th) | 16.4 (634) | 16.7 (614) | 10.5 (20) | 15.0 (670) | 15.5 (617) | 11.3 (53) |
  LGA (> 90th) | 4.8 (186) | 4.6 (170) | 8.4 (16) | 6.0 (269) | 5.5 (220) | 10.4 (49) |
  Missing | 18.6 (884) | 19.0 (864) | 9.5 (20) | 25.3 (1508) | 25.4 (1357) | 24.3 (151) |
Maternal characteristics | ||||||
Age at delivery (years), mean (SD) | 26.7 (6.0) | 26.6 (6.0) | 30.2 (5.4) | 28.0 (5.1) | 27.7 (5.0) | 30.7 (5.3) |
 Parity, % (N) | ||||||
  Primiparous | 48.5 (2238) | 48.6 (2144) | 46.1 (94) | 32.1 (1843) | 32.9 (1692) | 25.0 (151) |
  1 | 30.6 (1413) | 30.6 (1349) | 31.4 (64) | 27.5 (1577) | 28.3 (1455) | 20.2 (122) |
  2 | 13.1 (603) | 13.0 (573) | 14.7 (30) | 20.5 (1180) | 20.3 (1045) | 22.4 (135) |
  ≥ 3 | 7.8 (358) | 7.8 (342) | 7.8 (16) | 19.9 (1145) | 18.5 (949) | 32.5 (196) |
  Missing | 2.8 (135) | 2.8 (129) | 2.9 (6) | 3.6 (213) | 3.7 (195) | 2.9 (18) |
Height (cm), mean (SD) | 164.1 (6.2) | 164.2 (6.3) | 163.8 (6.1) | 159.4 (5.8) | 159.6 (5.8) | 157.9 (5.8) |
 Missing, % (N) | 12.6 (598) | 12.9 (587) | 5.2 (11) | 18.3 (1090) | 18.4 (981) | 17.5 (109) |
Body mass index (kg/m2), mean (SD) | 26.6 (6.0) | 26.5 (5.9) | 28.6 (6.3) | 25.5 (5.4) | 25.2 (5.3) | 28.2 (5.8) |
 Missing, % (N) | 14.5 (689) | 14.9 (674) | 7.1 (15) | 19.6 (1166) | 19.6 (1046) | 19.3 (120) |
Education, % (N) | ||||||
 < 5 GCSEs | 19.4 (799) | 19.6 (770) | 14.7 (29) | 24.7 (1208) | 23.9 (1045) | 31.5 (163) |
 5 GCSEs | 34.1 (1404) | 34.4 (1350) | 27.4 (54) | 30.9 (1513) | 30.9 (1353) | 31.0 (160) |
 A-level | 17.3 (714) | 17.4 (681) | 16.8 (33) | 12.8 (625) | 13.3 (583) | 8.1 (42) |
 Higher than A-level | 20.8 (857) | 20.3 (796) | 31.0 (61) | 28.4 (1389) | 28.7 (1255) | 25.9 (134) |
 Other | 8.3 (343) | 8.2 (323) | 10.2 (20) | 3.3 (163) | 3.3 (145) | 3.5 (18) |
 Missing | 13.3 (630) | 13.6 (617) | 6.2 (13) | 17.8 (1060) | 17.9 (955) | 16.9 (105) |
Maternal characteristics | ||||||
Smoking during pregnancy, % (N) | ||||||
  No | 67.4 (2836) | 67.0 (2682) | 76.2 (154) | 96.8 (4817) | 96.8 (4307) | 96.6 (510) |
  Yes | 32.6 (1371) | 33.0 (1323) | 23.8 (48) | 3.2 (159) | 3.2 (141) | 3.4 (18) |
  Missing | 11.4 (540) | 11.7 (532) | 3.8 (8) | 16.5 (982) | 16.6 (888) | 15.1 (94) |
 Any alcohol during pregnancy, % (N) | ||||||
  No | 33.3 (1399) | 33.1 (1323) | 37.6 (76) | 98.7 (4908) | 98.7 (4389) | 98.5 (519) |
  Yes | 66.7 (2802) | 66.9 (2676) | 62.4 (126) | 1.4 (67) | 1.3 (59) | 1.5 (8) |
  Missing | 11.5 (546) | 11.9 (538) | 3.8 (8) | 16.5 (983) | 16.6 (888) | 15.3 (95) |
Fasting glucose (mmol/L), mean (SD) | 4.40 (0.41) | 4.39 (0.37) | 4.86 (0.82) | 4.63 (0.61) | 4.53 (0.42) | 5.42 (1.17) |
Missing | 10.0 (475) | 10.3 (468) | 3.3 (7) | 8.0 (479) | 8.1 (448) | 5.0 (31) |
2-h postload glucose (mmol/L), mean (SD) | 5.44 (1.28) | 5.28 (1.07) | 8.55 (1.20) | 5.88 (1.64) | 5.48 (1.02) | 9.13 (2.13) |
 Missing | 10.1 (481) | 10.4 (474) | 3.3 (7) | 8.2 (486) | 8.5 (455) | 5.0 (31) |
 Hypertensive disorders of pregnancy, % (N) | ||||||
  No | 93.3 (4427) | 93.3 (4231) | 93.3 (196) | 94.7 (5644) | 94.8 (5057) | 94.4 (587) |
  Yes | 6.7 (320) | 6.7 (306) | 6.7 (14) | 5.3 (314) | 5.2 (279) | 5.6 (35) |