Table 3. Associations between self-reported exposure to non-chemical occupational factors and growth trajectories in estimated fetal weight, INMA, 2003-2008.
| Fetal growth trajectories | |||||
|---|---|---|---|---|---|
| 0-12 weeks | 12-20 weeks | 20-34 weeks | |||
| N | n exposed | % change (95% CI) | % change (95% CI) | % change (95% CI) | |
| Estimated fetal weight (EFW) | |||||
| Standing a | 1,593 | 972 | 0.3% (-0.8, 1.5%) | 0.2% (-1.3, 1.0%) | -0.1% (-1.0, 0.7%) |
| Heavy lifting (≥ 20 kg) a | 1,213 | 111 | -1.0% (-3.0, 1.1%) | -0.5% (-2.6, 1.6%) | -1.1% (-2.7, 0.4%) |
| Rotating shifts b | 1,574 | 186 | 0.6% (-1.0, 2.2%) | 1.0% (-0.7, 2.7%) | 0.6% (-0.8, 1.8%) |
| Any night work | 1,576 | 125 | 0.3% (-1.6, 2.2%) | 1.6% (-0.4, 3.6%) | 0.6% (-0.8, 2.0%) |
| Job strain and social isolation c | 1,589 | 381 | 0.3% (-0.9, 1.6%) | -0.9% (-2.2, 0.3%) | 0.7% (-0.2, 1.6%) |
| Biparietal diameter (BPD) | |||||
| Standing a | 1,598 | 976 | 0.1% (-0.9%, 1.1%) | 0.4% (-0.1%, 0.9%) | -0.2% (-0.5%, 0.1%) |
| Heavy lifting (≥ 20 kg) a | 1,217 | 112 | -0.8% (-2.7%, 1.1%) | -0.4% (-1.3%, 0.5%) | -0.1% (-0.7%, 0.5%) |
| Rotating shifts b | 1,579 | 187 | 0.5% (-0.9%, 2.0%) | 0.1% (-0.6%, 0.8%) | 0.0% (-0.4%, 0.5%) |
| Any night work | 1,581 | 126 | 0.6% (-1.1%, 2.3%) | 0.2% (-0.7%, 1.0%) | 0.0% (-0.6%, 0.5%) |
| Job strain and social isolation c | 1,594 | 383 | -0.2% (-1.3%, 0.9%) | 0.0% (-0.5%, 0.6%) | 0.0% (-0.4%, 0.3%) |
| Abdominal circumference (AC) | |||||
| Standing a | 1,600 | 977 | 0.3% (-0.7%, 1.2%) | -0.2% (-0.7%, 0.3%) | 0.1% (-0.2%, 0.5%) |
| Heavy lifting (≥ 20 kg) a | 1,217 | 112 | -0.4% (-2.2%, 1.4%) | 0.1% (-0.8%, 1.1%) | -0.3% (-1.0%, 0.4%) |
| Rotating shifts b | 1,581 | 187 | 0.8% (-0.6%, 2.2%) | 0.4% (-0.4%, 1.1%) | 0.5% (0.0%, 1.0%) |
| Any night work | 1,583 | 126 | 0.5% (-1.2%, 2.1%) | 0.5% (-0.4%, 1.4%) | 0.3% (-0.3%, 0.9%) |
| Job strain and social isolation c | 1,596 | 384 | 0.2% (-0.8%, 1.3%) | -0.3% (-0.8%, 0.3%) | 0.3% (-0.1%, 0.7%) |
| Femur length (FL) | |||||
| Standing a | 1,599 | 976 | 0.4% (-2.0%, 2.7%) | 0.1% (-0.5%, 0.6%) | -0.2% (-0.5%, 0.2%) |
| Heavy lifting (≥ 20 kg) a | 1,218 | 112 | -1.3% (-5.5%, 3.0%) | -0.8% (-1.9%, 0.3%) | -0.9% (-1.6%, -0.2%) |
| Rotating shifts b | 1,580 | 187 | 0.7% (-2.7%, 4.1%) | 0.4% (-0.4%, 1.2%) | -0.2% (-0.7%, 0.3%) |
| Any night work | 1,582 | 126 | -0.8% (-4.8%, 3.3%) | 0.7% (-0.3%, 1.7%) | 0.1% (-0.5%, 0.7%) |
| Job strain and social isolation c | 1,595 | 383 | 0.8% (-1.7%, 3.4%) | -0.4% (-1.0%, 0.3%) | 0.2% (-0.2%, 0.5%) |
CI: Confidence interval; Models are adjusted for maternal age, country of birth, education, pre-pregnancy BMI, gestational weight gain, smoking during pregnancy, alcohol use during pregnancy and parity.
a Frequent (2-4 h day) or very frequent (>4 h day) exposure compared to infrequent (<2 h day) or no exposure.
b Rotating versus fixed shift.
c Self-reported exposure to at least 3 psychosocial conditions and at least one lack of support condition compared to self-reported exposure to <3 psychosocial conditions or no lack of support conditions.