Hypertensive disorders of pregnancy are an important cause of severe morbidity, long-term disability and death among both pregnant women and their babies, and account for approximately 14% of all maternal deaths worldwide. Improving care for women around the time of childbirth is a necessary step towards achievement of the health targets of the Sustainable Development Goals (SDGs). Efforts to prevent and reduce morbidity and mortality during pregnancy and childbirth could also help address the profound inequities in maternal and perinatal health globally. To achieve these goals, healthcare providers, health managers, policy-makers and other stakeholders need up-to-date and evidence-based recommendations to inform clinical policies and practices. In 2019, the Executive Guideline Steering Group (GSG) on WHO maternal and perinatal health recommendations prioritized issuing new WHO recommendations on antihypertensive drugs for non-severe (mild to moderate) hypertension during pregnancy in response to new important evidence on this intervention. For this guideline, non-severe hypertension and mild to moderate hypertension is used interchangeably, defined as diastolic blood pressure of 90–109 mmHg.