Preeclampsia
Definition
Preeclampsia is high blood pressure and protein in the urine that develops after the 20th week of pregnancy.
Alternative Names
Toxemia; Pregnancy-induced hypertensionCauses
The exact cause of preeclampsia is not known. Possible causes include:
- Autoimmune disorders
- Blood vessel problems
- Diet
- Genes
Preeclampsia occurs in a small percentage of pregnancies. Risk factors include:
- First pregnancy
- Multiple pregnancy (twins or more)
- Obesity
- Older than age 35
- Past history of diabetes, high blood pressure, or kidney disease
Symptoms
Symptoms of preeclampsia can include:
- Headaches
- Swelling of the hands and face (edema)
- Weight gain
- More than 2 pounds per week
- Sudden weight gain over 1 - 2 days
Note: Some swelling of the feet and ankles is considered normal with pregnancy.
Other symptoms that can occur with this disease:
- Abdominal pain
- Agitation
- Decreased urine output
- Nausea and vomiting
- Vision changes
Exams and Tests
- Increase in blood pressure
- Higher than normal liver enzymes
- Platelet count less than 100,000 (thrombocytopenia)
- Protein in the urine (proteinuria)
- Swelling in the upper body
- Weight gain
Treatment
The only way to cure preeclampsia is to deliver the baby. However, if that delivery would be very early (premature), the disease can be managed by bed rest, close monitoring, and delivery as soon as the fetus has a good chance of surviving outside the womb. Sometimes, medicines are prescribed to lower the mother's blood pressure.
The pregnant mother is usually admitted to the hospital, but some women may be allowed to stay at home with careful monitoring of their blood pressure, urine, and weight, and the baby.
Ideally, the condition is managed until the baby can be delivered after the 37th week of pregnancy.
Labor may be induced if any of the following occur:
- Abdominal pain
- Abnormal biophysical profile (a test to monitor the health of the fetus)
- Abnormal liver function tests
- Diastolic blood pressure greater than 100 mmHg consistently for a 24-hour period, or any confirmed reading over 110 mmHg
- Eclampsia
- Failure of the fetus to grow
- Fluid in lungs (pulmonary edema)
- HELLP syndrome
- Increase in the level of creatinine in the blood
- Low platelet count (thrombocytopenia)
- Low urine production or severe protein in the urine, suggesting decline in kidney function
- Persistent or severe headache
Delivery is the treatment of choice for women with severe preeclampsia who are between 32 - 34 weeks pregnant.
For those who are less than 24 weeks pregnant, inducing labor is recommended, although the chance that the fetus will survive is very small.
Pregnancies between weeks 24 and 34 are considered a "gray zone." Prolonging a pregnancy has been shown to lead to problems for the mother in most cases. Infant death also can occur. The medical team and parents may decide to delay delivery to allow the fetus to develop.
Treatment during 24 - 34 weeks includes giving the mother steroid injections to help tspeed up the development of the baby's organs (including the lungs). The mother and baby are closely monitored for complications.
When labor and delivery are induced, the mother will be given medication to prevent seizures and to keep blood pressure under control. The decision to have a vaginal delivery versus cesarean section is based on the health of the mother, the baby's ability to tolerate labor, and other factors.
Outlook (Prognosis)
Death of the mother from preeclampsia is rare in the U.S. The infant's risk of death generally decreases as the pregnancy continues.
A woman with a history of preeclampsia is at risk for the condition again during future pregnancies.
Women who have high blood pressure problems during more than one pregnancy have an increased risk for high blood pressure when they get older.
Possible Complications
Preeclampsia can develop into eclampsia if the mother has seizures. Complications can occur if the baby is delivered prematurely.
Severe preeclampsia may lead to HELLP syndrome.
When to Contact a Medical Professional
Call your health care provider if you have symptoms of preeclampsia during your pregnancy.
Prevention
Although there is no known way to prevent preeclampsia, it is important for all pregnant women to start prenatal care early and continue it through the pregnancy. This allows the health care provider to find and treat conditions such as preeclampsia early.
References
Sibai BM. Hypertension. In: Gabbe SG, Niebyl JR, Simpson JL, eds. Obstetrics - Normal and Problem Pregnancies. 5th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2007:chap 33.
Cunnigham FG, Leveno KL, Bloom SL, et al . Hypertensive disorders in pregnancy. In: Cunnigham FG, Leveno KL, Bloom SL, et al, eds. Williams Obstetrics. 22nd ed. New York, NY; McGraw-Hill; 2005:chap 34.
Reviewed By: Linda Vorvick, MD, Seattle Site Coordinator, Lecturer, Pathophysiology, MEDEX Northwest Division of Physician Assistant Studies, University of Washington School of Medicine; and Susan Storck, MD, FACOG, Chief, Eastside Department of Obstetrics and Gynecology, Group Health Cooperative of Puget Sound, Redmond, Washington; Clinical Teaching Faculty, Department of Obstetrics and Gynecology, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
