FIGURE 65-6 A. Bacterial vaginosis. Microscopy reveals several squamous cells heavily studded with bacteria. Clue cells are covered to the extent that cell borders are blurred and nuclei are not visible (arrows). B. Trichomonads (arrows). (Reproduced with permission from McCord E, Rahn DO, Hoffman BL: Gynecologic infection. In Hoffman BL, Schorge JO, Bradshaw KD, et al (eds): Williams Gynecology, 3rd ed. New York, McGraw Hill Education, 2016. Photo contributors: Lauri Campagna and Mercedes Pineda, WHNP.)
The Nugent score, used primarily in research studies rather than clinical practice, is a system employed for diagnosing BV (Nugent, 1991). During microscopic examination of a gramstained vaginal discharge smear, scores are calculated by assessing bacteria staining and morphology.
Several adverse pregnancy-related health outcomes associated with BV are preterm birth, premature rupture of the membranes, and postpartum endometritis (Hillier, 1995; Leitich, 2003; Watts, 1990). It also increases susceptibility to STDs, including HIV (Atashili, 2008; Brotman, 2010). For women at low risk for preterm birth, however, treatment of BV does not reduce preterm birth rates (Brocklehurst, 2013; Carey, 2000). For high-risk women, evidence is conlicting. Currently, the American College of Obstetricians and Gynecologists (2016c), CDC, and U.S. Preventive Services Task Force do not recommend routine BV screening of asymptomatic gravidas-at either high or low risk for pre term delivery-to prevent preterm birth (Nygren, 2008; Workowski, 2015).
Treatment is reserved for symptomatic women. Preferred drugs are metronidazole, 500 mg twice daily orally for 7 days; metronidazole 0.75-percent gel, one applicator intravaginally, daily for 5 days; or clindamycin 2-percent cream, one applicator intravaginally nightly for 7 days. Alternatives are clindamycin, 300 mg orally twice daily for 7 days, or 100-mg clindamycin ovules placed intravaginally nightly for 3 days (Workowski, 2015). It is still debated whether BV is a sexually transmitted infection. But, treatment of a male partner does not appear to lower recurrence rates (Amaya-Guio, 2016).
Vaginitis caused by Trichomonas vaginalis is common, and its prevalence in the United States approximates 3 percent in nonpregnant and pregnant women (llsworth, 2009; Satterwhite, 2013). The prevalence is higher in those older than 30 years compared with younger women. Risks include black race, douching, and greater number of lifetime sexual partners (Sutton, 2007). Among women, frequent sites of infection include the urethra, endocervix, and vagina. Symptomatic vaginitis is characterized by yellow purulent discharge, pruritus, vulvovaginal erythema, and colpitis macularis, which is often termed a "strawberry cervix" and reflects a patchy, maculoerythematous ectocervix (W0Iner-Hanssen, 1989).