Syphilis during Pregnancy: A Study of 879,831 Pregnant Women in Brazil

Abstract

Background: The World Health Organization (WHO) estimates that approximately 350 million new cases of curable sexually transmitted disease (STD) are reported annually in individuals aged 15 to 49 years. Furthermore, the WHO estimates that syphilis during pregnancy causes more than 300,000 fetal and newborn deaths annually and increases the risk of premature death for approximately 215,000 children. In Brazil, more than 100,000 cases were reported during pregnancy between 2005 and 2014. In 2013 alone, approximately 14,000 cases of syphilis in children younger than one year were reported. The present study evaluated the prevalence of syphilis in pregnant women and identified factors involved in the dynamics of disease maintenance. Material and Methods: This retrospective ecological study included 879,831 pregnant women who underwent prenatal examinations between 2003 and 2016 in the state of Goias, located in the midwestern region of Brazil with an estimated population of 6.7 million inhabitants. Results: Approximately 67% of the pregnant women in the state of Goias underwent prenatal screening tests during the study period. The study included 821,785 (93.4%) women: 58,046 (6.6%) were excluded owing to data inconsistencies. Overall, 12,933 women tested positive for syphilis immunoglobulin M and G (IgM, IgG) via recombinant enzyme-linked immunosorbent assay screening; 6,501 cases were confirmed venereal disease research laboratory and fluorescent treponemal antibody absorption tests. The mean prevalence of syphilis in the study period was approximately 0.80%, ranging from a minimum and maximum of 0.22% (95% confidence interval [CI] 0.14-0.35) and 1.24% (95% CI 1.15-1.30) in 2013 and 2015, respectively. Conclusions: The rate of detection of syphilis cases in pregnant women in Brazil has increased in recent years. The severity of the current situation requires intensification of preventive actions to decrease morbidity and mortality in pregnant women with syphilis and, consequently, to avoid transmission to newborns. In this study, the mother’s age at pregnancy and the reported number of spontaneous abortions strongly influenced the observed prevalence.