Eclampsia refers to the occurrence of one or more generalized convulsions and/or coma in the setting of preeclampsia and in the absence of other neurologic conditions. The clinical manifestations can appear anytime from the second trimester to the puerperium. In the past, eclampsia was thought to be the end result of preeclampsia (hence the nomenclature); however, it is now clear that seizures should be considered merely one of several clinical manifestations of severe preeclampsia (table 1), rather than a separate disease. Despite advances in detection and management, preeclampsia/eclampsia remains a common cause of maternal death .
The diagnosis and management of eclampsia will be reviewed here. Issues related to preeclampsia are discussed separately. (See "Preeclampsia: Pathogenesis" and "Preeclampsia: Clinical features and diagnosis" and "Preeclampsia: Management and prognosis" and "Preeclampsia: Prevention".)
INCIDENCE AND EPIDEMIOLOGY
An eclamptic seizure occurs in 2 to 3 percent of severely preeclamptic women not receiving anti-seizure prophylaxis; the seizure rate is estimated to be between 0 and 0.6 percent in women with preeclampsia without severe features (previously referred to as “mild” preeclampsia) . The incidence of eclampsia has been relatively stable at 1.6 to 10 cases per 10,000 deliveries in developed countries [3-8]. In developing countries, however, the incidence varies widely: from 6 to 157 cases per 10,000 deliveries [9-11].
Risk factors for eclampsia are similar to those for preeclampsia (table 2). Nonwhite, nulliparous women from lower socioeconomic backgrounds are the group at highest risk of developing eclampsia. Peak incidence is in the teenage years and low twenties, but there is also an increased incidence in women over 35 years of age.
Timing: antepartum, intrapartum, postpartum — Eclampsia prior to 20 weeks of gestation is rare and should raise the possibility of an underlying molar pregnancy or antiphospholipid syndrome. (See "Gestational trophoblastic disease: Epidemiology, clinical manifestations and diagnosis" and "Pregnancy in women with antiphospholipid syndrome".)