Syphilis Treatment in Pregnant Women

Treatment Regimens

The Centers for Disease Control and Prevention recommends penicillin G benzathine as the treatment for syphilis during pregnancy, with the dosage and administration depending on the stage of the disease, as it is the only proven effective medication to prevent mother-to-fetal transmission 1, 2
For primary, secondary, or early latent syphilis, penicillin G benzathine 2.4 million units IM in a single dose is recommended, with some specialists suggesting a second dose of 2.4 million units IM one week after the initial dose, especially in the third trimester 1, 2, 3, 4
For late latent or latent syphilis of unknown duration, penicillin G benzathine 7.2 million units in total, administered as 3 doses of 2.4 million units IM each, with intervals of one week, is recommended 2

The American College of Obstetricians and Gynecologists notes that there are no proven alternatives to penicillin for the treatment of syphilis during pregnancy, and women with a history of penicillin allergy should undergo desensitization and then be treated with penicillin 1, 4
Tetracycline, doxycycline, and erythromycin are contraindicated during pregnancy, and erythromycin should not be used because it does not reliably cure fetal infection 1, 3, 5

The Centers for Disease Control and Prevention recommends coordinated prenatal care and treatment follow-up, with serologic titers repeated in the third trimester and at delivery 1
Serologic titers may be checked monthly in women at high risk of reinfection or in areas with high syphilis prevalence 1

The American College of Obstetricians and Gynecologists recommends that all women undergo serologic testing for syphilis at the start of pregnancy, and in high-risk populations, testing should be done twice during the third trimester and at delivery 1
No newborn should be discharged from the hospital without the maternal serologic status having been determined at least once during pregnancy 1

The Centers for Disease Control and Prevention recommends that individuals exposed to a patient with primary, secondary, or early latent syphilis in the preceding 90 days should be treated presumptively, even if they are seronegative 2
Long-term sexual partners of patients with late syphilis should be clinically and serologically evaluated 2

The Centers for Disease Control and Prevention recommends a second dose of 2.4 million units IM one week after the initial dose for women in the third trimester, particularly for those with secondary syphilis, and for HIV-infected pregnant women 6, 7, 8, 9

The Centers for Disease Control and Prevention recommends that pregnant women with penicillin allergy must undergo skin testing and desensitization, then be treated with penicillin 8, 9
The Centers for Disease Control and Prevention advises against using tetracyclines and doxycycline due to hepatotoxicity to the mother and fetal bone/teeth staining, and against using erythromycin as it does not reliably cure fetal infection 6, 8, 9

The Centers for Disease Control and Prevention recommends that women seek immediate obstetric attention if they notice contractions or decreased fetal movements within 24 hours of treatment 7, 8, 9
The Centers for Disease Control and Prevention advises performing pretreatment ultrasound in viable pregnancies when feasible, particularly after 20 weeks gestation, and consulting with obstetric specialists for pregnancies with ultrasound abnormalities 8, 9

The Centers for Disease Control and Prevention recommends that all pregnant women be screened for syphilis at the first prenatal visit, and that high-risk populations require additional screening at 28-32 weeks gestation and at delivery 8, 9

The Centers for Disease Control and Prevention recommends checking serologic titers monthly until delivery to ensure adequate treatment response, and repeating titers in the third trimester and at delivery 6, 7

The Centers for Disease Control and Prevention advises against delaying treatment due to concerns about stillbirth risk from Jarisch-Herxheimer reaction, as untreated syphilis causes far greater fetal harm 6, 7
The Centers for Disease Control and Prevention recommends against treating with erythromycin, tetracyclines, or other non-penicillin regimens, as these do not prevent congenital syphilis 6, 8, 9
The Centers for Disease Control and Prevention advises against discharging a newborn without documented maternal syphilis screening 7, 8, 9