Changes in vaginal discharge are often caused by imbalance in the vaginal microflora, and laboratory testing is usually of little use, as most microbes detected are commensals. In-office diagnosis in general practice using wet mount microscopy and Amsel criteria is helpful and often sufficient to ensure correct diagnosis and treatment. Laboratory testing of vaginal discharge should only be performed, if sexually transmitted disease is suspected, if there is treatment failure or inconclusive wet mount prior to gynaecological surgery, and in pregnant women with recurrent miscarriage or preterm birth.