Table 2 Weight characteristics before, during and after the index pregnancy from GROW 2012–2013
From: Breastfeeding, socioeconomic status, and long-term postpartum weight retention
|  | All N = 2144 | Low SES N = 1048 | High SES N = 1096 | p-value |
|---|---|---|---|---|
Pre-pregnancy BMI, kg/m2 | 24.9 ± 0.13 | 25.9 ± 0.2 | 23.5 ± 0.14 |  < .0001 |
Pre-pregnancy weight (kg) | 65.6 ± 0.37 | 67.1 ± 0.56 | 63.4 ± 0.44 |  < .0001 |
Total gestational weight gain, kg | 14.2 ± 0.15 | 13.6 ± 0.23 | 15.0 ± 0.18 |  < .0001 |
GWG z-score | -0.23 ± 0.02 | -0.3 ± 0.04 | -0.13 ± 0.03 | 0.0005 |
IOM GWG Recommendations, N(%) | ||||
  Below | 355 (17) | 214 (20) | 141 (13) |  |
  Within | 813 (38) | 359 (34) | 454 (41) |  |
  Exceed | 976 (45) | 475 (45) | 501 (46) |  |
IOM Recommendations by BMI, N(%) | ||||
Pre-pregnancy BMI status: Under/Normal | ||||
  Below guidelines | 252 (19) | 135 (25) | 117 (15) |  |
  Within guidelines | 565 (44) | 202 (38) | 363 (47) |  |
  Exceed Guidelines | 482 (37) | 193 (36) | 289 (38) |  |
Pre-pregnancy BMI status: Overweight | ||||
  Below guidelines | 44 (8) | 37 (13) | 7 (3) |  |
  Within guidelines | 155 (31) | 86 (30) | 69 (30) |  |
  Exceed Guidelines | 321 (61) | 166 (57) | 155 (67) |  |
Pre-pregnancy BMI status: Obesity Class 1 | ||||
  Below guidelines | 30 (15) | 22 (16) | 8 (13) |  |
  Within guidelines | 50 (25) | 39 (28) | 11 (18) |  |
  Exceed Guidelines | 120 (60) | 77 (56) | 43 (69) |  |
Pre-pregnancy BMI status: Obesity Class 2/3 | ||||
  Below guidelines | 29 (23) | 20 (22) | 9 (27) |  |
  Within guidelines | 43 (34) | 32 (35) | 11 (32) |  |
  Exceed Guidelines | 53 (42) | 39 (43) | 14 (41) |  |
  Post-partum weight retention, kg | 4.02 ± 0.21 | 5.68 ± 0.33 | 1.83 ± 0.21 |  < 0.001 |
  Long term BMI, kg/m2 | 26.5 ± 0.14 | 28.2 ± 0.21 | 24.3 ± 0.15 |  < 0.001 |