Table 1.
Univariate Logistic Regression Analysis of risk factors associated with EPT in women undergoing cerclage in the training cohort.
| Variable | Deliver <28w (n = 63) | Deliver≥28w (n = 304) | OR (95%CI) | P-value | VIF | |
|---|---|---|---|---|---|---|
| Age, y | 32 (22, 41) | 31 (19, 48) | 1.02 (0.97, 1.08) | 0.414 | 2.93 | |
| ≥35 y, n (%) | 18 (28.57%) | 74 (24.34%) | 1.24 (0.68, 2.28) | 0.481 | 2.75 | |
| <35 y, n (%) | 45 (71.43%) | 230 (75.66%) | Reference | |||
| Gravidity | 3 (0, 9) | 3 (1, 9) | 0.93 (0.78, 1.11) | 0.934 | 5.31 | |
| Parity | 0 (0, 2) | 0 (0, 3) | 0.60 (0.35, 1.03) | 0.062 | 2.43 | |
| Pregestational BMI, kg/m2 | 23.43 (12.02, 39.35) | 22.27 (14.17, 34.05) | 1.07 (1.00. 1.15) | 0.049 | 1.19 | |
| IVF | Yes, n (%) | 14 (22.22%) | 37 (12.17%) | 2.06 (1.04, 4.10) | 0.039 | 1.22 |
| No, n (%) | 49 (77.78%) | 267 (87.83%) | Reference | |||
| History of prior early abortion, n | 0 (0, 7) | 0 (0, 5) | 1.10 (0.88, 1.37) | 0.398 | 3.98 | |
| History of prior second-trimester loss, n | 1 (0, 4) | 1 (0, 3) | 1.72 (1.26, 2.35) | 0.001 | 1.89 | |
| History of preterm birth, n | 0 (0, 1) | 0 (0, 2) | 0.52 (0.21. 1.28) | 0.153 | 1.40 | |
| History of hysteroscopic surgery, n | 0 (0, 5) | 0 (0, 5) | 1.23 (0.91, 1.67) | 0.175 | 1.22 | |
| History of corn biopsy | Yes, n (%) | 2 (3.17%) | 14 (4.61%) | 0.68 (0.15, 3.07) | 0.615 | 1.17 |
| No, n (%) | 61 (96.83%) | 290 (95.39%) | Reference | |||
| PCOS | Yes, n (%) | 1 (1.59%) | 10 (3.29%) | 0.47 (0.60–3.77) | 0.481 | 1.07 |
| No, n (%) | 62 (98.41%) | 294 (96.71%) | Reference | |||
| History of surgery for uterine malformation/fibroids | Yes, n (%) | 1 (1.59%) | 2 (0.66%) | 2.44 (0.22–27.28) | 0.470 | 1.10 |
| No, n (%) | 62 (98.41%) | 302 (99.34%) | Reference | |||
| History of failure of cervical cerclage | Yes, n (%) | 5 (7.94%) | 10 (3.29%) | 2.53 (0.84, 7.69) | 0.101 | 1.05 |
| No, n (%) | 58 (92.06%) | 294 (96.71%) | Reference | |||
| Intervals from prior pregnancy | No prior pregnancy | 10 (15.87%) | 33 (10.86%) | Reference | 0.050 | 1.29 |
| 0–6 month | 6 (9.52%) | 22 (7.24%) | 0.90 (0.29, 2.83) | |||
| 6–12 month | 18 (28.57%) | 52 (17.11%) | 1.14 (0.47, 2.78) | |||
| >12 month | 29 (46.03%) | 197 (64.80%) | 0.49 (0.22, 1.09) | |||
| Gestational weeks at cerclage, wk | 17 (12, 24) | 16 (11, 25) | 1.02 (0.95, 1.09) | 0.542 | 2.12 | |
| Cervical length, cm | 1.80 (0, 4.30) | 2.50 (0, 5.70) | 0.68 (0.54, 0.85) | 0.001 | 2.46 | |
| Cervical dilation, cm | 0 (0, 8) | 0 (0, 6) | 1.95 (1.54, 2.43) | <0.001 | 1.58 | |
| WBC before cerclage, ∗10ˆ9/L# | 9.90 (6.20, 15.50) | 9.69 (4.7, 17.80) | 1.01 (0.89, 1.15) | 0.862 | 1.80 | |
| CRP before cerclage, mg/L# | 4.90 (0.60, 39.10) | 3.40 (0.10, 33.70) | 1.11 (1.05, 1.16) | <0.001 | 1.24 | |
| NLR before cerclage | 5.11 (2.55, 9.30) | 4.56 (1.00, 17.92) | 1.17 (1.02, 1.34) | 0.023 | 2.54 | |
| PLR before cerclage | 155.63 (84, 348.18) | 138.35 (25.09, 464) | 1.01 (1.00, 1.01) | 0.001 | 2.19 | |
| Microbiological infection | Yes, n (%) | 19 (30.16%) | 89 (29.28%) | 1.04 (0.58, 1.89) | 0.889 | 1.08 |
| No, n (%) | 44 (69.84%) | 215 (70.72%) | Reference | |||
Abbreviations: EPT, extremely preterm birth; BMI, body mass index; IVF, in-vitro fertilization; WBC, white blood cells; CRP, C-reactive protein; PCOS, polycystic ovary syndrome; NLR, neutrophil-lymphocyte ratio; PLR, platelet-lymphocyte ratio; OR, odds ratio; CI, confidence interval; VIF, variance inflation factor.
∗P value < 0.05.