Eclampsia is pregnancy-related seizure activity that is caused by severe preeclampsia. Less than 1% of women who have preeclampsia experience seizures.¹ Eclampsia is life-threatening for both a mother and her fetus. During a seizure, the oxygen supply to the fetus is drastically reduced.

Sudden seizures can occur before, during, or (rarely) up to 6 weeks after delivery (postpartum). Postpartum seizures are most common during the first 48 hours after delivery.

A large, worldwide study has shown that magnesium sulfate treatment cuts the risk of eclampsia in half for women who have preeclampsia. In the study, the chance of eclampsia decreased regardless of how severe the woman's preeclampsia was.²

What happens during a seizure

A woman with eclampsia has a type of seizure called a grand mal seizure, which begins with a sudden loss of consciousness.

• During the first 15 to 30 seconds of a seizure, the entire body stiffens as the muscles contract. The back and neck arch. The woman may cry out as the vocal cords contract or may turn blue if she is having difficulty breathing.
• During the next 30 to 45 seconds, the muscles jerk, or convulse, in a rhythmic pattern. While the muscles are jerking, the woman may bite her tongue or lose bladder or bowel control.
• An entire seizure lasts 1 to 2 minutes or longer. After the seizure, the woman will be unresponsive at first but will gradually wake up within 10 to 15 minutes. She may be sleepy, confused, or dazed. She may also feel tired, weak, or moody and may have a headache and muscle aches for the next 24 hours.