Characteristics of mothers with syphilis associated with CS
| Characteristic | CS (n=39) | Non-CS (n=1519) | χ²/Z value | P value |
| Mother’s age (years, %) | 25.136 | <0.001 | ||
| ≤24 | 17 (7.1) | 224 (92.9) | ||
| 25–29 | 9 (2.3) | 380 (97.7) | ||
| 30–34 | 7 (1.4) | 477 (98.6) | ||
| ≥35 | 6 (1.4) | 438 (98.6) | ||
| Ethnicity (%) | 0.183* | 0.422 | ||
| Han | 36 (2.4) | 1445 (97.6) | ||
| others | 3 (3.9) | 74 (96.1) | ||
| Marital status (%) | 9.272* | 0.002 | ||
| Married | 29 (2.1) | 1374 (97.9) | ||
| Unmarried | 10 (6.5) | 145 (93.5) | ||
| Educational attainment (%)† | 0.643 | 0.887 | ||
| Primary school or below | 4 (3.1) | 126 (96.9) | ||
| Middle school | 17 (2.6) | 637 (97.4) | ||
| High school | 11 (2.7) | 394 (97.3) | ||
| Bachelor or above | 4 (1.8) | 214 (98.2) | ||
| Employed (%)† | 0.025 | 0.875 | ||
| No | 20 (2.4) | 816 (97.6) | ||
| Yes | 10 (2.3) | 434 (97.7) | ||
| Migrant resident (%) | 1.734* | 0.188 | ||
| Yes | 6 (4.6) | 124 (95.4) | ||
| No | 33 (2.3) | 1395 (97.7) | ||
| History of syphilis infections (%) | 14.005 | <0.001 | ||
| Yes | 7 (0.9) | 733 (99.1) | ||
| No | 32 (3.9) | 786 (96.1) | ||
| Maternal syphilis stage (%) | 3.553 | 0.059 | ||
| Latent | 27 (2.1) | 1234 (97.9) | ||
| Stage I–III | 12(4) | 285(96) | ||
| Titres of TRUST before treatment (%) | 67.220 | <0.001 | ||
| <1:8 | 9 (0.7) | 1196 (99.3) | ||
| ≥1:8 | 30 (8.5) | 323 (91.5) | ||
| Period of initiating treatment (%) | 115.138* | <0.001 | ||
| Before 28 weeks | 9 (0.8) | 1187 (99.2) | ||
| After 28 weeks | 3 (1.8) | 160 (98.2) | ||
| No treatment | 27 (13.6) | 172 (86.4) | ||
| Drugs (%) | 10.382 | 0.006 | ||
| Penicillin G | 21 (1.5) | 1393 (98.5) | ||
| Ceftriaxone | 1 (11.1) | 8 (88.9) | ||
| Erythromycin | 2 (7.1) | 26 (92.9) | ||
| Mode of delivery (%) | 1.017 | 0.313 | ||
| Vaginal delivery | 25 (2.9) | 846 (97.1) | ||
| Caesarean section | 14 (2.1) | 665 (97.9) | ||
| Newborn’s sex (%) | 0.676 | 0.411 | ||
| Boy | 24 (2.8) | 834 (97.2) | ||
| Girl | 15 (2.1) | 685 (97.9) | ||
| Newborn receiving treatment (%) | 0.019 | 0.892 | ||
| Yes | 27 (2.5) | 1036 (97.5) | ||
| No | 12 (2.4) | 483 (97.6) | ||
| Preterm birth (%) | 83.112* | <0.001 | ||
| Yes | 22 (13.3) | 144 (86.7) | ||
| No | 17 (1.2) | 1375 (98.8) | ||
Significant P-values are in bold-type.
*The χ² correction for continuity tests were used for categorical variables.
†There were missing values in each group.
CS, congenital syphilis; TRUST, toluidine red unheated serum test.