High blood pressure, otherwise known as hypertension, is one of the most common gestational diseases during pregnancy and can have detrimental consequences to the health of the mother and the fetus if not managed properly. There are different classifications of hypertension seen in pregnancy. These classifications can be based on the presence or absence of certain signs and symptoms such as the presence or absence of proteinuria or the presence or absence of seizures. Other types of hypertensions in pregnancy can also be described based on whether the hypertension was present before or after pregnancy. While some remain unclassified. The aim of this paper is to show the current methods of diagnosing hypertension in pregnancy with the importance of an early diagnosis. This paper will also show the consequences of high blood pressure on maternal health and foetal health. In addition, this paper also aims to show the most up-to-date management techniques used in gestational hypertension as well as the steps to take in preventing the progression of gestational hypertension to worse states, namely pre-eclampsia and eclampsia. It will be based on different publications, research papers and information from various internationally recognised bodies that deal with hypertension and obstetrics and gynaecology matters such as the American Heart Association (AHA), Committee on Terminology of the American College of Obstetricians and Gynaecologists (ACOG) and the National Institute for Health and Clinical Excellence (NICE).