Table 1.
Demographic, prior pregnancy, and antenatal characteristics of the study cohort. Data are n(%) unless otherwise specified; the denominator is provided, as applicable, if there are missing values for a variable.
| Characteristic |
Non-Hispanic Black patients n = 51 |
Patients of other race and/or ethnic groups n = 104 |
p-value |
|---|---|---|---|
| Maternal age, mean years (± SD) | 31.4 ± 6.2 | 32.1 ± 6.6 | 0.546 |
| Married | 23 (45.1) | 77 (75.5) | <0.001 |
| Low socioeconomic status* | 14 (27.5) | 35 (34.3) | 0.391 |
| Smoked cigarettes during pregnancy | 5 (9.8) | 14 (13.9) | 0.475 |
| Pre-pregnancy body mass index, median kg/m2 (IQR) | 32.7 (26.0, 39.1) | 28.3 (23.2, 33.3) | 0.003 |
| No prior pregnancy to reach at least 14 weeks’ gestation | 11 (21.6) | 22 (21.2) | 0.953 |
| Prior preterm birth <37 weeks’ gestation** | 38 (95.0) | 79 (96.3) | 0.726 |
| Gestational age of earliest prior preterm birth, median weeks (IQR)† | 22.1 (19.4, 30.7) | 26.0 (20.9, 32.6) | 0.257 |
| Shortest endovaginal cervical length, median mm (IQR)‡ | 28 (9, 37) | 31.5 (16, 40) | 0.568 |
| Endovaginal cervical length less than 25 mm‡ | 21/47 (44.7) | 39/94 (41.5) | 0.718 |
| Cervical cerclage placed | 26 (51.0) | 41 (39.4) | 0.172 |
| Received 17-alpha hydroxyprogesterone caproate** | 33/38 (86.8) | 67/79 (84.8) | 0.770 |
| Received vaginal progesterone | 17 (33.3) | 24 (23.1) | 0.174 |
* defined as one or more of the following: no healthcare insurance, annual household income <$24,000 annually, or less than high school education
**among 122 patients with at least one prior pregnancy reaching 14 weeks’ gestation
†among patients with ≥1 prior preterm birth and prior history available
‡among 141 patients with ≥1 endovaginal cervical length 16.0–23.9 weeks’ gestation