Characteristics | Frequency (percentagea) | P-valuec | |
---|---|---|---|
 | Birth cohort sample (Years 2006 to 2008) n = 1565 | Deliveries in regionb (Year 2006) n = 8608 |  |
Gender of infant | Â | Â | Â |
   Male | 764 (49.9%) | 4462 (51.8%) | 0.079 |
   Female | 782 (50.1%) | 4145 (48.2%) |  |
   Missing data | 19 | 0 |  |
Maternal age | Â | Â | Â |
   <20 years | 87 (5.7%) | 512 (5.9%) | 0.239 |
   20-24 years | 325 (21.1%) | 1608 (18.7%) |  |
   25-29 years | 424 (27.6%) | 2388 (27.7%) |  |
   30-34 years | 427 (27.8%) | 2515 (29.2%) |  |
   ≥35 years | 274 (17.8%) | 1584 (18.4%) |  |
   Missing data | 28 | 0 |  |
Birth weight | Â | Â | Â |
   <2500 g | 39 (2.5%) | 450 (5.5%) | <0.0005 |
   2500-3999 g | 1266 (81.7%) | 7073 (82.2%) |  |
   ≥4000 g | 244 (15.8%) | 1060 (12.3%) |  |
   Missing data | 16 | 2 |  |
Gestational age at birth | Â | Â | Â |
   <28 weeks | 0 (0.0%) | 59 (0.7%) | <0.0005 |
   28-36 weeks | 38 (2.4%) | 536 (6.2%) |  |
   37-41 weeks | 1505 (97.2%) | 7963 (92.5%) |  |
   ≥42 weeks | 6 (0.4%) | 45 (0.5%) |  |
   Missing data | 16 | 4 |  |
Plurality | Â | Â | Â |
   Singleton | 1532 (98.5%) | 8388 (97.4%) | 0.016 |
   Multiple | 24 (1.5%) | 220 (2.6%) |  |
   Missing data | 9 | 0 |  |
Outcome | Â | Â | Â |
   Live birth | 1554 (99.9%) | 8547 (99.3%) | 0.007 |
   Stillbirth | 2 (0.1%) | 61 (0.7%) |  |
   Missing data | 9 | 0 |  |