Syphilis and gonorrhea were prominently mentioned in the irst edition of this book, with special consideration for their harmful efects on fetal development. Although Williams confined his discussion to these two infections, today, sexually transmitted diseases (STDs) include chlamydial and trichomonal infections and viral STDs such as hepatitis B, human immunodeiciency virus (HIV), herpes simplex virus (HSV), and human papillomavirus (HPV) infections. In some form, all can be injurious to the mother or fetus and thus should be aggressively sought and treated. In many instances, recommended therapies are provided in guidelines from the Centers for Disease Control and Prevention (CDC) and listed throughout the chapter.
Vertical transmISSIOn refers to passage from the mother to her fetus of an infectious agent through the placenta, during labor or delivery, or by breastfeeding. Treatment of most STDs is clearly associated with improved pregnancy outcome and prevention of perinatal morbidity. Logically, education, screening, treatment, and prevention are essential components of prenatal care.
Despite the availability of adequate therapy for decades, syphilis remains a major issue for both mother and fetus. From 2001 through 2015, the primary and secondary syphilis rates have risen almost yearly (Centers for Disease Control and Prevention, 2016c). In the United States in 2015, the combined rate for both of these among women was 1.8 cases per 100,000 persons (de Voux, 2017). For congenital syphilis, after a nadir in 2012, rates have also risen yearly to reach 12.4 cases per 100,000 live births in 2015. Of risks, higher congenital syphilis rates are linked to inadequate prenatal care, black or Hispanic race, and lack of treatment (Su, 2016). Similarly, syphilis remains a signiicant global health problem, with many countries reporting high numbers of new infections (Newman, 2015; World Health Organization, 2012).
Syphilis is caused by the spirochetal bacterium Treponema pallidum. Minute abrasions on the vaginal mucosa provide an entry portal, and cervical eversion, hyperemia, and friability raise transmission risk. Spirochetes replicate and then disseminate through lymphatic channels within hours to days. The incubation period is 3 to 4 weeks depending on host factors and inoculum size.
he early stages of syphilis include primary, secondary, and early latent syphilis. hese are associated with high spirochete loads, and partner transmission rates approximate 30 to 60 percent (Garnett, 1997; Singh, 1999). In late-stage disease, transmission rates decline because of smaller inoculum sizes.
FIGURE 65-1 Primary syphilis. Photograph of a chancre with a raised, firm border and smooth, red base.
Maternal syphilis can cause fetal infection by several routes. Spirochetes readily cross the placenta to cause congenital infection. Although transplacental transmission is the most common route, neonatal infection may follow after contact with spirochetes through lesions at delivery or across the placental membranes. Fetal infection develops in >50 percent of untreated early syphilis cases and in 10 percent of late latent disease (Fiumara, 1975; Hollier, 2001).
This is staged according to clinical features and disease duration.
1. Primary syphilis is diagnosed by its characteristic chancre, which develops at the inoculation site. This solitary, painless