How Is Eclampsia Treated For a Safe Delivery?

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Question: How is Eclampsia Treated?


Eclampsia is a treatable condition, and appropriate treatment is essential to avoid dangerous complications for both mother and baby. Treating eclampsia follows a well-defined set of guidelines. In general, these guidelines aim to accomplish four goals:

  • Preventing low oxygen levels (hypoxia) in the mother
  • Controlling maternal blood pressure
  • Preventing ongoing seizures
  • Preparing to deliver the baby by the safest method possible

While these four goals provide the framework for properly treating eclampsia, the only “cure” for the condition is to deliver the baby, which must be done as quickly as possible while still assuring as much safety as possible for both mother and baby.

Preventing Seizures

Hypoxia, blood pressure spikes, and changes in blood flow to the baby are all expected and likely during an active seizure. For this reason, controlling and preventing additional seizures is a primary focus of eclampsia treatment. Women with eclampsia have at least one seizure, and treatment focuses on preventing additional seizures from occurring.

Magnesium sulfate is used to prevent additional seizures. In recent years, doctors have disagreed about whether magnesium sulfate or more traditional anti-seizure medications (diazepam, phenytoin) should be preferred. Obstetricians favored magnesium, while neurologists favored the more traditional approach.

However, a large amount of clinical evidence now conclusively supports the use of magnesium sulfate as the safest and most effective drug for preventing seizures in pregnant women.

Overall, the data shows that magnesium sulfate can reduce the risk of having ongoing seizures by up to 66%. When compared to other anti-seizure medications, magnesium sulfate has been shown to be more effective and to reduce the risk of other possible complications.

Controlling Blood Pressure

Women with eclampsia require good blood pressure control to:

  • Avoid future seizures
  • Prevent stroke

Elevated blood pressure makes seizures both more likely and more difficult to control. At the same time, women with eclampsia seem to be especially sensitive to the effects of elevated blood pressure, and some studies estimate that 20% of eclampsia related deaths are the direct result of stroke caused by increased blood pressure.

While it is well known that good blood pressure control is essential in cases of eclampsia, there is little consensus about target blood pressure values or how high blood pressure can be before requiring emergency treatment. In general, aggressive therapy is recommended for systolic blood pressures greater than 160 mmHg or diastolic pressures greater than 105 mmHg. In cases where high blood pressure existed before the pregnancy, these numbers are more flexible because the mother’s cardiovascular system is more “used to” elevated pressure and better able to withstand the extra stress. Similarly, if the patient’s normal blood pressure tends to run lower than average, these numbers need to be adjusted downward.

In general, studies have shown that while it is necessary to control very high pressures in women with eclampsia, there appears to be no benefit from attempting to control blood pressure that is only mildly elevated.

In contrast, some studies have shown that being too aggressive in trying to control mildly elevated blood pressure in these situations can actually cause unexpected complications such as hypotension. Again, there is no clear “cutoff” value for the difference between “mildly elevated” and “very high” blood pressure –- these decisions follow the general numbers listed above and depend on the specific patient.

While several options are available for treating high blood pressure in eclampsia, hydralazine and labetalol are the preferred drugs. Calcium channel blockers are generally avoided because they can interact with magnesium sulfate and cause low blood pressure.

Delivering the Baby

Delivery is the only cure for eclampsia, and it must take place as soon as possible after treatment begins. Delivery is always the ultimate goal of treatment, and will be attempted regardless of how far along the pregnancy has progressed. Unfortunately, in cases where the baby is less than 32 weeks old, the baby faces all of the risks associated with premature birth. While vaginal delivery is sometimes possible, clinical evidence has shown that unless the mother is already near term, cesarean delivery is usually the preferred option.

After delivery, both mother and baby are monitored closely for any signs of complication or difficulty. While complications sometimes occur, most cases of eclampsia will resolve after delivery. The mother’s urine output is considered to be an important sign of recovery, and will be watched carefully. An output greater than 4L per day is considered a very good sign. Because seizures can still sometimes occur after giving birth, anti-seizure medications are usually continued for up to two days after delivery.

Learn More About Eclampsia


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