Table 2 Offspring birth weight and preterm birth according to maternal age and pre-pregnancy body mass index
|  | Underweight, n (%) (BMI < 18.5 kg/m2)* | Normal weight, n (%) (BMI 18.5-24.9 kg/m2) | Overweight, n (%) (BMI 25.0-29.9 kg/m2) |
|---|---|---|---|
SGA | |||
 Overall | 165 (7.71) | 618 (4.29) | 90 (4.24) |
 Age group, years | |||
  < 30 | 62 (6.99) | 193 (4.31) | 27 (4.07) |
  30-34 | 71 (8.11) | 254 (4.04) | 42 (4.65) |
  35-37 | 23 (8.16) | 109 (4.88) | 14 (4.03) |
  ≥ 38 | 9 (9.38) | 62 (4.37) | 7 (3.32) |
AGA | |||
 Overall | 1760 (82.20) | 11,313 (78.47) | 1475 (69.41) |
 Age group, years | |||
  < 30 | 736 (82.98) | 3470 (77.42) | 473 (71.23) |
  30-34 | 728 (83.11) | 4952 (78.84) | 617 (68.33) |
  35-37 | 219 (77.66) | 1756 (78.60) | 238 (68.59) |
  ≥ 38 | 77 (80.21) | 1135 (79.93) | 147 (69.67) |
LGA | |||
 Overall | 216 (10.09) | 2486 (17.24) | 560 (26.35) |
 Age group, years | |||
  < 30 | 89 (10.03) | 819 (18.27) | 164 (24.70) |
  30-34 | 77 (8.79) | 1075 (17.12) | 244 (27.02) |
  35-37 | 40 (14.18) | 369 (16.52) | 95 (27.38) |
  ≥ 38 | 10 (10.42) | 223 (15.70) | 57 (27.01) |
Preterm | |||
 Overall | 121 (5.65) | 1064 (7.38) | 231 (10.87) |
 Age group, years | |||
  < 30 | 47 (5.30) | 322 (7.18) | 66 (9.94) |
  30-34 | 50 (5.71) | 441 (7.02) | 97 (10.74) |
  35-37 | 19 (6.74) | 175 (7.83) | 40 (11.53) |
  ≥ 38 | 5 (5.21) | 126 (8.87) | 28 (13.27) |