| Characteristics | Preterm delivery without HCA (n = 20) | Preterm delivery with HCA (n = 20) | p-value |
| Maternal age* | 24.55 ± 6.47 | 22.10 ± 5.99 | 0.222 |
| Marital status |
|
|
|
| Single | 27.78% (5/18) | 40% (8/20) | 0.506 |
| Married | 72.22% (13/18) | 60% (12/20) | |
| Ethnicity |
|
|
|
| White | 95% (19/20) | 85% (17/20) | 0.605 |
| Non-white | 5% (1/20) | 15% (3/20) | |
| Type of delivery |
|
|
|
| Vaginal | 75% (15/20) | 60% (12/20) | 0.501 |
| Cesarean | 25% (5/20) | 40% (8/20) | |
| Gestational age at delivery (days)+ | 238.5 (177 - 258) | 233 (182 - 255) | 0.715 |