Syphilis in pregnancy

Background

Risk of transmission to fetus
- Primary and secondary syphilis: 70 to 100%
- Early latent syphilis: 40%
- Late latent syphilis: 10%

Antimicrobials
- For primary, secondary, or early latent syphilis: benzathine penicillin G 2.4 million units IM weekly for 1-2 doses
- For late latent, latent syphilis with unknown duration, or tertiary syphilis not involving the CNS: benzathine penicillin G 2.4 million units IM weekly for 3 doses
- For tertiary neurosyphilis, treat as usual
Monitor response to treatment with RPR serology
- Primary, secondary, and early latent
  - 1, 3, 6, and 12 months after treatment; or monthly until delivery, if high risk for reinfection
  - Primary should decrease 4-fold at 6 months and 8-fold at 12 months
  - Secondary should decrease 8-fold at 6 months and 16-fold at 12 months
  - Early latent should decrease 4-fold at 12 months
- Late latent: at delivery, 12 months, and 24 months
- Neurosyphilis: repeat lumbar puncture every 6 months until parameters normalize
  - CSF-VDRL titre should decrease 4-fold within a year but may take years to revert to negative
Postpartum, follow guidelines for congenital syphilis to decide whether and how to treat the neonate