15. Sexually transmitted infections

Sexually transmitted infections (STIs) form a large burden for sexually active women globally. Public health efforts are of great importance to limit their detrimental effects at a population level. Both gynaecologists and obstetricians should be aware of the nature and adverse outcomes STIs can have in their patients. The asymptomatic nature of many STIs can hinder a timely diagnosis. In this chapter, key populations at risk for STIs and the most commonly used preventive interventions are highlighted. Subsequently the most common pathogens are discussed such as C. trachomatis, N. gonorrhoea, T. vaginalis, T. pallidum, herpes simplex viruses and human immunodeficiency virus (HIV). These pathogens are addressed where relevant in paragraphs that cover the syndromic spectrum of STIs: from lower tract infections such as vulvitis and vaginitis, to upper tract infections as cervicitis and pelvic inflammatory disease, to systemic infections caused by syphilis and HIV. Lastly, STIs in pregnancy are covered.