Table 2 Association between rate of GWG and PTB – stratified by pre-pregnancy BMIa
GWG rate (kg/week) | Preterm birth N (%) | Crude ORc (95 % CI) | Adjusted OR (95 % CI) | |
|---|---|---|---|---|
Categoryb | Range | |||
Total (N = 17475) | ||||
Insufficient | - | 90 (3.9) | 1.46 (1.12,1.92) | 1.41 (1.07,1.85) |
Adequate | - | 137 (2.7) | reference | reference |
Excessive | - | 374 (3.7) | 1.38 (1.13,1.68) | 1.37 (1.11,1.68) |
Underweight (N = 4335) | ||||
Insufficient | <0.44 | 38 (4.0) | 1.61 (1.01,2.56) | 1.54 (0.97,2.47) |
Adequate | 0.44–0.58 | 36 (2.5) | reference | reference |
Excessive | >0.58 | 87 (4.5) | 1.81 (1.22,2.68) | 1.93 (1.29,2.88) |
Normal weight (N = 11559) | ||||
Insufficient | <0.35 | 44 (3.5) | 1.25 (0.87,1.80) | 1.22 (0.85,1.76) |
Adequate | 0.35–0.5 | 97 (2.8) | reference | reference |
Excessive | >0.5 | 232 (3.4) | 1.22 (0.96,1.55) | 1.20 (0.94,1.54) |
Overweight/Obese (N = 1581) | ||||
Insufficient | - | 8 (9.5) | 4.21 (1.23,14.42) | 3.92 (1.13,13.67) |
Adequate | - | 4 (2.4) | reference | reference |
Excessive | - | 55 (6.0) | 1.72 (0.62,4.81) | 1.52 (0.53,4.32) |