Incidence, risk factors, and associated complications of eclampsia.

OBJECTIVE: To estimate trends in incidence and identify risk factors and maternal and neonatal consequences of eclampsia in Canada.

METHODS: We conducted a population-based cohort study of all women and their newborns (N=1,910,729) delivered in the hospital in Canada (excluding Quebec) from 2003 to 2009. The data were obtained from the Canadian Institute for Health Information. Logistic models were used to examine the association with potential determinants and consequences of eclampsia.

RESULTS: The incidence of eclampsia declined dramatically from 12.4 per 10,000 deliveries in 2003 to 5.9 in 2009. Among singleton deliveries, nulliparity (adjusted odds ratio [OR] 2.3; 95% confidence interval [CI] 2.0-2.6), anemia (adjusted OR 2.4; 95% CI 2.0-3.0), and existing heart disease (adjusted OR 4.8; 95% CI 2.9-7.3) increased the risk of eclampsia. The declining trend in eclampsia remained unchanged after accounting for changes in potential determinants and risk factors during the study period. Eclampsia was associated with increased risks of maternal death (adjusted OR 26.8; 95% CI 9.7-73.8), assisted ventilation (adjusted OR 102.3; 95% CI 78.2-133.8), respiratory distress syndrome (adjusted OR 36.2; 95% CI 15.3-85.3), acute renal failure (adjusted OR 20.9; 95% CI 11.4-38.3), obstetric embolism (adjusted OR 9.1; 95% CI 4.1-19.9), and other complications. Adverse neonatal outcomes associated with eclampsia included neonatal death (adjusted OR 2.9; 95% CI 1.6-5.5), respiratory distress syndrome (adjusted OR 5.1; 95% CI 4.1-6.3), and small-for-gestational age birth (adjusted OR 2.6; 95% CI 2.3-3.0).

CONCLUSION: Despite declining incidence and improved care of women with eclampsia, the condition remains strongly associated with serious adverse consequences.