Bacterial Vaginosis

Bacterial vaginosis (BV) is a shift in the vaginal microbiota rather than an infection caused by one organism. Protective lactobacilli decrease, while anaerobic organisms such as Gardnerella vaginalis, Prevotella species, and Mobiluncus species increase. Lactobacilli normally help maintain an acidic vaginal environment. When they decline, vaginal pH rises and anaerobic metabolism produces volatile amines. Those amines explain the characteristic fishy odour, which may become more noticeable after intercourse or when an alkaline substance is present. The typical discharge is homogeneous, thin, and gray or gray-white. BV often causes less vulvar inflammation than candidiasis, so intense erythema, marked swelling, or severe itch should make the nurse question whether BV is the only diagnosis. BV can recur. It is associated with increased risk of pelvic inflammatory disease and acquisition of HIV, chlamydia, or HPV. During pregnancy, BV is associated with adverse outcomes including preterm birth; a pregnant patient requires appropriate obstetric involvement rather than treatment decisions based only on a previous episode.