Preeclampsia (pre-e-KLAMP-si-a) is a complication of pregnancy that first develops without noticeable symptoms. Symptoms when present may include high blood pressure (hypertension), headaches, changes in vision, and excess protein in the urine, indicating kidney damage. If preeclampsia is severe enough to affect brain function, eclampsia (e-KLAMP-si-a) can develop causing seizures or coma.
Preeclampsia is diagnosed when the woman has persistent high blood pressure combined with high levels of protein in the urine, or decreased platelet counts, liver or kidney problems, fluid in the lungs, convulsions, or visual problems during pregnancy. In the past, preeclampsia was also called toxemia of pregnancy or pregnancy-induced hypertension (PID), but these terms are no longer used by medical professionals. Not all women diagnosed with preeclampsia go on to have the convulsions/seizures of eclampsia. Preeclampsia begins after the 20th week of pregnancy but can occur as late as 4 to 6 weeks after the baby is delivered.
Left untreated, preeclampsia can lead to eclampsia and serious—even fatal—complications for both mother and baby. The only cure for preeclampsia is delivery of the baby.
The cause of eclampsia is not clearly understood. Risk factors associated with eclampsia include diabetes and other disorders that affect the blood vessels; factors in the brain and nervous system; autoimmune disorders (such as rheumatoid arthritis, multiple sclerosis, and systemic lupus erythematosus); diet; and a family history of preeclampsia.
According to the American Pregnancy Association, preeclampsia affects at least 5 to 8 percent of all pregnancies in the United States. Preeclampsia occurs more often in pregnant women who have the following characteristics:
Signs of preeclampsia include a weight gain of more than two pounds each week; headaches, nausea, and vomiting; swelling of the hands and face; stomach pain; extremely high blood pressure (160 mm Hg or higher); visual changes (such as blurred vision, inability to tolerate bright light, and seeing flashing spots); and abnormal results from blood and urine tests. Convulsions are the major indicator of eclampsia.
Diagnosis is made on the basis of the reported signs and symptoms, evaluation of blood pressure, and results of laboratory studies on blood and urine. The diagnosis of preeclampsia/eclampsia is usually made after the 20th week of pregnancy, but it may be made earlier if the characteristic signs and symptoms have been observed.
Women with preeclampsia/eclampsia are more likely to experience a premature birth—that is, the baby is born before it is fully developed. Women who are at risk of or who have preeclampsia may be advised to do the following:
The best way to prevent preeclampsia/eclampsia is to start routine prenatal care (in other words, care of mother and baby during pregnancy and before the baby's birth) early during the pregnancy. This approach enables healthcare providers (doctors and nurse midwives * ) to identify the risk of preeclampsia/eclampsia and to start treatment early. Doctors may recommend the following preventive measures, not only to women at risk of preeclampsia/eclampsia, but also to all pregnant women. Some of these measures are similar to the means of treatment:
The best treatment to prevent preeclampsia from progressing to eclampsia is to deliver the baby. If the baby is too undeveloped to be delivered, the mother is monitored closely and may be treated with medications to lower her blood pressure and to prevent convulsions/seizures.
See also Autoimmune Disorders: Overview • Diabetes • Hypertension • Obesity • Pregnancy
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American Pregnancy Association. 1425 Greenway Drive, Suite 440, Irving, TX 75038. Toll-free: 800-672-2296. Website: http://americanpregnancy.org (accessed March 24, 2016).
Eunice Kennedy Shriver National Institute of Child Health and Human Development. 31 Center Dr., Building 31, Room 2A32, MSC 2425, Bethesda, MD 20892-2425. Toll-free: 800-370-2943. Website: (accessed August 3, 2016).
Preeclampsia Foundation. 6905 N. Wickham Road, Suite 302, Melbourne, FL 32940. Toll-free: 800-665-0341. Website: http://www.preeclampsia.org (accessed March 24, 2016).
* seizures (SEE-zhurs) are sudden bursts of disorganized electrical activity that interrupt the normal functioning of the brain, often leading to uncontrolled movements in the body and sometimes a temporary change in consciousness. Also called convulsions.
* pregnancy is the period of time between conception and delivery of a fetus or baby. In humans, normal pregnancy is approximately nine months.
* nurse midwife is a nurse with specialized knowledge and experience in the care of pregnant women before, during, and after delivering a baby.