Associations between Antenatal Syphilis Test Results and Adverse Pregnancy Outcomes in Western Kenya.

Maternal syphilis remains a major contributor to poor pregnancy outcomes. Syphilis point-of-care (POC) tests are now used for pregnancy screening; the effect of screening on outcomes is unclear. We enrolled women presenting to antenatal care (ANC) in a matched cohort study at a single site in Kenya tested by either a syphilis-only or an HIV/syphilis dual POC test. Syphilis POC-positive women (patients) were matched 1:2 with POC-negative women (control subjects) on gravidity, gestational age, and HIV status, and were monitored through delivery. Syphilis serum testing was performed every 8 weeks. Pregnancy outcomes were assessed up to 1 month after delivery and compared using prevalence ratios. A total of 151 women were enrolled (51 patients and 100 control subjects) at a mean of 22 weeks gestation; 24% were HIV positive and 40% were paucigravid. A positive Treponema pallidum hemagglutination test was more common among patients (64.7%) than control subjects (11.1%, P < 0.001). Only two women met the definition for incident syphilis. Pregnancy outcomes were available for 147 women. The prevalence of low birthweight (LBW) was greater among patients (15.2%) than control subjects (5.4%, P = 0.052). Of the 109 women with concordant syphilis POC and Treponema pallidum hemagglutination test results at ANC enrollment, LBW prevalence was significantly greater among test-positive (25%) than test-negative (4.9%) women (adjusted prevalence ratio, 5.84; 95% CI, 1.08-31.5). Despite treatment with penicillin, latent syphilis at ANC enrollment was associated with a more than 5-fold increased risk of LBW. Alternate implementation strategies for syphilis POC testing may be necessary to realize the potential of ANC syphilis screening to improve pregnancy outcomes.

Duke Scholars

Author Steve M Taylor Medicine, Infectious Diseases