Hypertension in pregnancy and its management

Introduction The most common medical complications of pregnancy is hypertension and its disorder which are an important cause of maternal and perinatal morbidity and mortality worldwide.1 During normal gestation period systolic pressure changes slightly whereas diastolic pressure drops by 10 mm Hg early in 13 to 20 weeks and increases again to pre-pregnancy levels in the third trimester. [1] The term hypertension in pregnancy is actually a very broad term which has further conditions in which blood pressure varies accordingly. All current definitions and classification schemes have certain pitfalls as they relate to clinical diagnosis and management. Nevertheless, a recent report by the Working Group on High Blood Pressure in Pregnancy recommended using the classification system proposed by the American College of Obstetricians and Gynecologists even though this classification is not accepted in many countries outside the United States.2 In this review, hypertensive disorders of pregnancy will be divided into three categories: chronic hypertension, gestational hypertension, and preeclampsia (Table 1). Chronic Hypertension The incidence of chronic hypertension in gestation women ranges from 1-5%. [3] The rates are higher in older women, obese women, and black women.8 It is difficult to diagnose chronic hypertension in pregnant women who never regularly monitored their blood pressure. In such cases, the diagnosis is usually based on the presence of hypertension before 20 weeks’ gestation. In some women, however, hypertension before 20 weeks’ gestation may be the first manifestation of preeclampsia. [4] Furthermore, because of the normal physiologic decrease in blood pressure during the 2nd trimester, majority of women with chronic hypertension have normal blood pressure before 20 weeks’ gestation. On the basis of either the systolic or the diastolic blood pressure non-pregnant women and in men, hypertension is often classified as mild, moderate, severe, or very severe. Whereas pregnant women suffering from chronic hypertension are considered either mild or severe. However there is no agreed statement on definition of mild hypertension, there is agreement that a diastolic blood pressure of 110 mm Hg or higher (Korotkoff phas