The exact cause of eclampsia is not known. Factors that may play a role include:

• Blood vessel problems
• Brain and nervous system (neurological) factors
• Diet
• Genes

Eclampsia follows a condition called preeclampsia. This is a complication of pregnancy in which a woman has high blood pressure and other findings.

Most women with preeclampsia do not go on to have eclampsia (seizures). It is hard to predict which women will. Women at high risk of seizures often have severe preeclampsia with findings such as:

• Abnormal blood tests
• Headaches
• Very high blood pressure
• Vision changes
• Abdominal pain

Your chances of getting preeclampsia increase when:

• You are 35 or older.
• You are African American.
• This is your first pregnancy.
• You have diabetes, high blood pressure, or kidney disease.
• You are having more than 1 baby (such as twins or triplets).
• You are a teen.
• You are obese.
• You have a family history of preeclampsia.
• You have autoimmune disorders.
• You have undergone in vitro fertilization.
• You have history of a clotting disorder.

Symptoms of eclampsia include:

• Seizures
• Severe agitation
• Unconsciousness
• Altered mental status and confusion

Most women will have these symptoms of preeclampsia before the seizure:

• Headaches
• Nausea and vomiting
• Stomach pain
• Swelling of the hands and face
• Vision problems, such as loss of vision, blurred vision, double vision, or missing areas in the visual field

The health care provider will do a physical exam to look for causes of seizures. Your blood pressure and breathing rate will be checked regularly.

Blood and urine tests may be done to check:

• Blood clotting factors
• Blood creatinine
• Hematocrit
• Uric acid
• Liver function
• Platelet count
• Protein in the urine
• Hemoglobin level

The main treatment to prevent severe preeclampsia from progressing to eclampsia is giving birth to the baby. Letting the pregnancy go on can be dangerous for you and the baby.

You may be given medicine to prevent seizures. These medicines are called anticonvulsants.

Your provider may give you medicine to lower high blood pressure. If your blood pressure stays high, delivery may be needed, even if it is before the baby is due.

Women with eclampsia or preeclampsia have a higher risk for:

• Separation of the placenta (placenta abruptio)
• Premature delivery that leads to complications in the baby
• Blood clotting problems
• Stroke
• Infant death
• Maternal death

Contact your provider or go to the emergency room if you have any symptoms of eclampsia or preeclampsia. Emergency symptoms include seizures or decreased alertness.

Seek medical care right away if you have any of the following:

• Bright red vaginal bleeding
• Little or no movement in the baby
• Severe headache
• Severe pain in the upper right abdominal area
• Vision loss
• Nausea or vomiting

Getting medical care during your entire pregnancy is important in preventing complications. This allows problems such as preeclampsia to be detected and treated early.

Getting treatment for preeclampsia may prevent eclampsia.

Pregnancy - eclampsia; Preeclampsia - eclampsia; High blood pressure - eclampsia; Seizure - eclampsia; Hypertension - eclampsia

American College of Obstetricians and Gynecologists; Task Force on Hypertension in Pregnancy. Hypertension in pregnancy. Report of the American College of Obstetricians and Gynecologists' Task Force on Hypertension in Pregnancy. Obstet Gynecol. 2013;122(5):1122-1131. PMID: 24150027 pubmed.ncbi.nlm.nih.gov/24150027/.

Harper LM, Tita A, Karumanchi SA. Pregnancy-related hypertension. In: Lockwood CJ, Copel JA, Dugoff L, eds. Creasy and Resnik's Maternal-Fetal Medicine: Principles and Practice. 9th ed. Philadelphia, PA: Elsevier; 2023:chap 45.

Henn MC, Lall MD. Complications of pregnancy. In: Walls RM, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 10th ed. Philadelphia, PA: Elsevier; 2023:chap 173.

Sibai BM. Preeclampsia and hypertensive disorders. In: Landon MB, Galan HL, Jauniaux ERM, et al, eds. Gabbe's Obstetrics: Normal and Problem Pregnancies. 8th ed. Philadelphia, PA: Elsevier; 2021:chap 38.

Updated by: LaQuita Martinez, MD, Department of Obstetrics and Gynecology, Emory Johns Creek Hospital, Alpharetta, GA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.