Table 1.
Maternal characteristics of patients with PPROM based on IPI (N = 6707).
| Characteristic | IPI ≤6 months (N = 2104) |
IPI 7–23 months (N = 1566) |
IPI ≥24 months (N = 3127) |
p value |
|---|---|---|---|---|
| Maternal age (years) | ||||
| ≤35 | 1862 (88.5%) | 1385 (88.4%) | 2482 (79.4%) | <.001 |
| 36–44 | 240 (11.4%) | 181 (11.6%) | 636 (20.3%) | |
| ≥45 | 2 (0.1%) | 0 (0%) | 9 (0.3%) | |
| Maternal race | ||||
| Caucasian | 1403 (66.7%) | 1015 (64.8%) | 1969 (63.0%) | .005 |
| African American | 560 (26.6%) | 423 (27.0%) | 858 (27.4%) | |
| Hispanic | 2 (0.1%) | 5 (0.3%) | 5 (0.2%) | |
| Asian | 24 (1.1%) | 11 (0.7%) | 36 (1.1%) | |
| Other | 115 (5.5%) | 112 (7.1%) | 259 (8.3%) | |
| BMI (kg/m2) | ||||
| 18.5–24.9 | 882 (42.5%) | 657 (42.5%) | 1201 (38.8%) | .001 |
| <18.5 | 91 (4.4%) | 95 (6.1%) | 163 (5.3%) | |
| 25.0–29.9 | 479 (23.1%) | 321 (20.7%) | 665 (21.5%) | |
| ≥30.0 | 623 (30.0%) | 665 (21.5%) | 1063 (34.3%) | |
| Use of social services | 1297 (61.6%) | 1025 (65.4%) | 1910 (61.1%) | .01 |
| Tobacco use | 146 (6.9%) | 122 (7.8%) | 350 (11.2%) | <.001 |
| Prior preterm birth | 73 (3.5%) | 104 (6.6%) | 232 (7.4%) | <.001 |
Data are N (%).
BMI: body mass index; IPI: interpregnancy interval; PPROM: preterm premature rupture of membranes.