Table 3 Adjusted odds ratios and corresponding 95% confidence intervals* for NICU admissions
From: Trends of preterm birth and low birth weight in Japan: a one hospital-based study
1997-2000 | 2001-2003 | 2004-2006 | 2007-2010 | |
|---|---|---|---|---|
All births | 1 (Ref) | 1.06 (0.94, 1.19) | 0.81 (0.71, 0.92) | 0.84 (0.75, 0.95) |
PTB | ||||
Separated by type | ||||
Medically indicated PTB 37 wk | 1 (Ref) | 1.12 (0.67, 1.87) | 0.47 (0.30, 0.72) | 0.44 (0.29, 0.68) |
Spontaneous PTB 37 wk | 1 (Ref) | 0.80 (0.49, 1.29) | 0.64 (0.39, 1.05) | 1.05 (0.66, 1.65) |
Separated by gestational week | ||||
PTB 34–36 wk | 1 (Ref) | 1.02 (0.70, 1.47) | 0.67 (0.47, 0.96) | 0.77 (0.54, 1.09) |
PTB 28–33 wk | 1 (Ref) | 0.57 (0.12, 2.67) | 0.07 (0.02, 0.26) | 0.14 (0.04, 0.50) |
PTB 22–27 wk | 1 (Ref) | 0.77 (0.09, 6.56) | 1.57 (0.21, 11.48) | 5.22 (0.38, 71.55) |
LBW | 1 (Ref) | 1.24 (0.98, 1.56) | 0.84 (0.67, 1.05) | 0.97 (0.78, 1.20) |