Table 2.
Adjusted oddsa of preterm birth among US military family infants born after in utero exposure to stress
| Characteristic | All infants n = 164743 |
Infants born pretermb n = 11453 |
OR [95% CI] | ||
| n | % | n | % | ||
| In utero exposure to September 11, 2001c | |||||
| No | 111413 | (67.6) | 7692 | (67.2) | 1.00 |
| Yes | 53330 | (32.4) | 3761 | (32.8) | 1.02 [0.98,1.06] |
| Maternal age | |||||
| <35 years | 151571 | (92.0) | 10429 | (91.1) | 1.00 |
| ≥ 35 years | 13172 | (8.0) | 1024 | (8.9) | 1.22 [1.14, 1.31] |
| Maternal military status | |||||
| Civilian/married to active duty | 133152 | (80.8) | 9125 | (79.7) | 1.00 |
| Active duty | 31591 | (19.2) | 2328 | (20.3) | 1.02 [0.97, 1.07] |
| Military parent's education level | |||||
| Bachelor's or above | 30097 | (18.3) | 1761 | (15.4) | 1.00 |
| Some college | 6715 | (4.1) | 467 | (4.1) | 1.09 [0.95, 1.25] |
| High school or less | 127931 | (77.7) | 9225 | (80.5) | 1.10 [0.99, 1.23] |
| Military parent's race/ethnicity | |||||
| White/non-Hispanic | 108252 | (65.7) | 7172 | (62.6) | 1.00 |
| Black/non-Hispanic | 30300 | (18.4) | 2670 | (23.3) | 1.30 [1.24, 1.37] |
| Hispanic | 16097 | (9.8) | 985 | (8.6) | 0.88 [0.82, 0.95] |
| Asian/Pacific Islander | 6183 | (3.8) | 388 | (3.4) | 0.91 [0.82, 1.02] |
| Other | 3911 | (2.4) | 238 | (2.1) | 0.89 [0.77, 1.01] |
| Military parent's service branch | |||||
| Army | 61822 | (37.5) | 4412 | (38.5) | 1.00 |
| Navy/Coast Guard | 41294 | (25.1) | 3031 | (26.5) | 1.03 [0.99, 1.09] |
| Air Force | 42103 | (25.6) | 2630 | (23.0) | 0.89 [0.85, 0.94] |
| Marine Corps | 19524 | (11.9) | 1380 | (12.0) | 1.01 [0.95, 1.08] |
| Military parent's pay grade | |||||
| Officer | 27752 | (16.8) | 1601 | (14.0) | 1.00 |
| Enlisted | 136991 | (83.2) | 9852 | (86.0) | 1.14 [1.02, 1.27] |
| Military parent's occupation | |||||
| All others | 115269 | (70.0) | 8150 | (71.2) | 1.00 |
| Health care specialists | 14366 | (8.7) | 985 | (8.6) | 1.01 [0.94,1.03] |
| Combat specialists | 35108 | (21.3) | 2318 | (20.2) | 0.98 [0.94,1.04] |
aBased on multivariable logistic regression.
b Defined as estimated gestational age (EGA) less than 37 completed weeks.
cExposed infants were in utero from 0 to 36 weeks EGA on September 11, 2001.
Unexposed infants were in utero from 0 to 36 weeks EGA on September 11, 2000 or September 11, 2002.
OR, odds ratio; CI, confidence interval.