الفهرس Only 14 pages are availabe for public view
 |  | from | 163 |  |  |
| | | from | 163 | | |
Abstract
Hypertensive disorders in pregnancy are major cause of maternal death and fetal prematurity. Death associated with hypertensive disorders may be duo to cerebrovascular event, renal or hepatic failure, HELLP syndrome, or other complications of hypertension.
Hypertension during pregnancy is classified according to degree of high blood pressure, associated signs and symptoms, and time of onset during pregnancy to:
1- chronic hypertension: high blood pressure detected before the first 20 weeks of gestation.
2- Gestational hypertension: high blood pressure that begins after 20 weeks of gestation and is not accompanied by protein in the urine.
3- Preeclampsia: high blood pressure that begins after 20 weeks of gestation and is accompanied by proteinuria.
4- Preeclampsia superimposed on chronic hypertension: It is characterized by new onset of proteinuria (or by sudden increase in the protein level, if proteinuria already is present), an acute increase in the level of hypertension or development of HELLP syndrome.
5- Eclampsia: a life threatening condition defined by the presence of convulsions and typically preceded by preeclampsia.
The aetiology of preeclampsia is still unknown but there are several risk factors that explain the occurrence of pregnancy induced hypertension, some of this risk factors include age and parity, family history, genetic factors, obstetric factors, race, obesity, smoking and preexisting medical condition.
Numerous theories are suggested to explain the etiology of preeclampsia but they still under-consideration, from these theories: defect in placentation and placental perfusion, endothelial cell activation, procoagulant proteins and plasminogen activators and prostaglandin theory.
Pathological changes occur in preeclampsia eclampsia are very dangerous and include: haemodynamic changes, haemoconcentration, coagulation changes and thrombocytopenia also there are pathological changes in multiorgans e.g. liver, brain and kidney in the form of hepatic rupture, subcapsular hematoma and liver failure, pathological changes in the brain in the form of hypertensive encephalopathy, coma and blindness.