Table 2

Univariable logistic analyses of the risk factors for congenital syphilis

VariablesOR (95% CI)p Values
Current age1.02 (0.93 to 1.11)0.736
Education
 Secondary school or belowReference
 High school or above0.47 (0.21 to 1.04)0.063
History of other STD
 NoReference
 Yes0.40 (0.05 to 3.02)0.374
Extramarital sexual relations
 NoReference
 Yes1.20 (0.57 to 2.54)0.637
Numbers of pregnancies
 1Reference
 21.39 (0.42 to 4.56)0.588
 31.14 (0.33 to 3.90)0.834
 41.27 (0.33 to 4.87)0.733
 ≥50.87 (0.15 to 4.91)0.872
History of APOs
 NoReference
 Yes0.97 (0.36 to 2.60)0.948
Stage of maternal syphilis
 Early (<2 years)5.01 (2.15 to 11.69)<0.001
 Late (≥2 years or unknown)Reference
Log (1/T)*11.18 (5.16 to 24.24)<0.001
GW1.1 (1.06 to 1.15)<0.001
GW×log (1/T)1.09 (1.06 to 1.11)<0.001
  • * The values were transformed by the log (the reciprocal of the TRUST titre in mothers).

  • The gestational week (GW) at treatment for maternal syphilis.

  • The interaction between GW and log (1/T).

  • APOs, adverse pregnancy outcomes; STD, sexually transmitted disease; TRUST, toluidine red unheated serum test.