Table 1.
Comparison of epidemiological characteristics
| Data | Nifedipine group (N=103) | Placebo group (N=103) |
|---|---|---|
| Maternal age (years; mean) | 27.1 (SD 5.73) | 25.6 (SD 5.85) |
| Gravid (mean) | 2.28 (SD 1.17) | 1.87 (SD 0.89) |
| Parity (mean) | 0.89 (SD 0.76) | 0.70 (SD 0.79) |
| Previous abortion, n (%) | 28 (27.1%) | 15 (14.5%) |
| Previous cesarean section, n (%) | 27 (25.9%) | 17 (16.5%) |
| History of preterm birth, n (%) | 13 (12.5%) | 8 (7.7%) |
| Smoking, n (%) | 4 (1.94%) | 2 (3.85%) |
| Infection, n (%) | 15 (14.0%) | 17 (16.5%) |
| Mean gestational age (weeks) | 33.6 (SD 2.48) | 33.4 (SD 2.52) |
| Body weight (kg) | 67.1 (SD 14.25) | 64.0 (SD 10.19) |
| Body mass index (kg/m2) | 26.9 (SD 0.53) | 26.2 (SD 0.39) |
| Initial dilatation of cervix (cm) | 0.20 (SD 0.40) | 0.17 (SD 0.37) |
Abbreviation: SD, standard deviation.