Efficacy of treatment for syphilis in pregnancy

Objective: To evaluate prospectively the Centers for Disease Control and Pr evention (CDC) recommended regimens for the treatment of antepartum syphili s and prevention of congenital syphilis. Methods: This was a prospective evaluation of recommended syphilis treatmen t regimens from September I, 1987, to August 31, 1989, at Parkland Memorial Hospital, Dallas, Texas. Women with syphilis were staged and treated accor ding to CDC recommendations. Treatment included 2.4 million units of intram uscular (IM) benzathine penicillin G for primary, secondary, or early laten t (less than I year) syphilis. Women with late latent (uncertain or longer than 1 year) syphilis were treated with 7.2 million units of benzathine pen icillin G IM over 3 weeks. Results: During the study period, 448 of 28,552 women (1.6%) delivered were diagnosed with syphilis. One hundred eight were diagnosed at delivery and treated postpartum. The remaining 340 (75.9%) gravidas with untreated syphi lis attending prenatal clinic comprised the study group. The success of the rapy in preventing congenital syphilis was as follows: primary syphilis, 27 of 27; secondary syphilis, 71 of 75; early latent syphilis, 100 of 102; an d late latent syphilis, 136 of 136. The success rate for all stages of syph ilis was 334 of 340 (98.2%). The success rate of therapy in secondary syphi lis was significantly different from that of the other groups (P = .03). Tw o of the six fetal treatment failures produced preterm stillborns. Only one maternal treatment failure occurred, in a human immunodeficiency virus-inf ected woman. Conclusion: The CDC-recommended regimens for the prevention of congenital s yphilis and treatment of maternal infection are effective, but the highest risk of fetal treatment failure exists with maternal secondary syphilis. (C ) 1999 by The American College of Obstetricians and Gynecologists.