Alternative Names pregnancy-induced hypertension (PIH), toxaemia
Definition Preeclampsia is high blood pressure condition that develops during pregnancy. There is also swelling of the body and protein in the urine. The condition usually occurs after the 20th week of pregnancy. Preeclampsia can develop into eclampsia(seizures).
What is going on in the body? Preeclampsia develops in 5-10% of pregnant women, usually in the first pregnancy. The cause is not known. Preeclampsia can be mild or severe. The disease can affect the brain, kidneys, liver, and lungs. The woman can have seizures. When preeclampsia develops, there may be serious problems for mother and baby.
What are the signs and symptoms of the disease? The symptoms of preeclampsia may include:
sudden weight gain due to rapid development of oedema (fluid in tissues)
What can be done to prevent the disease? There are no known ways to prevent preeclampsia. All pregnant women should have early antenatal care. Blood pressure changes should be watched closely. Finding and treating the disease early can stop serious complications for mother and baby.
How is the disease diagnosed? A healthcare professional will look for the following:
blood pressure greater than 140/90
swelling in the face and hands
protein in the urine
dropping level of platelets, one of the cells in the blood that is important for blood clotting
high haemoglobin, or quantity of the pigment that gives red blood cells their colour. The doctor will also check the woman's percent of red blood cells in the blood.
anaemia, or low red blood cell counts
high levels of clotting breakdown products in the blood
What are the long-term effects of the disease? Both mother and baby are at risk. Risks include:
intrapartum foetal distress, or abnormalities noted on the heart rate of the baby during labour
stillbirth
intrauterine growth retardation, a lack of normal growth of the baby within the womb
suffocation at birth, or asphyxia
development of eclampsia, which is potentially fatal for mother and child
What are the risks to others? Though an affected mother and her baby are at risk, preeclampsia and eclampsia are not contagious.
What are the treatments for the disease? Giving birth is the only cure for preeclampsia. The safety of the mother should be considered first. Delivering a healthy baby that does not need intensive long-term care should follow. Preeclampsia limits blood flow to the placenta and the foetus. If a woman has symptoms, flow may already be reduced by 50%. The doctor may decide to induce labour, or to wait for labour to occur naturally. The following factors will make the decision:
condition of the mother and foetus
foetal age
presence of labour
severity of the disease
dilation of the cervix
maternal desire
If the symptoms are mild, outpatient treatment is common. This includes bed rest at home and biweekly examinations in the doctor's office. If symptoms do not improve, hospitalisation may be needed. Tests for foetal maturity will help decide if early delivery is possible. Early delivery will prevent more serious problems. Serial ultrasounds are used to monitor growth and placental blood flow.
In severe cases, action is needed. Delivery may be induced if any of the following occur:
Delaying delivery when the foetus is mature causes problems for mother and baby.
Treating severe preeclampsia means controlling the woman's blood pressure. A surgical delivery may be needed if blood pressure is not controlled. Medications to prevent eclampsia include magnesium sulfate and other drugs to prevent seizures. In addition, medications may be prescribed to lower blood pressure.
What are the side effects of the treatments? Side effects from magnesium sulfate include nausea, vomiting, respiratory depression, and respiratory arrest. These can be avoided with careful monitoring of serum magnesium levels. Other medications also have side effects, such as allergic reactions and stomach upset. Surgery carries a risk of infection, bleeding or even death.
What happens after treatment for the disease? A woman may be at risk for developing eclampsia up to 6 weeks after delivery. The mother needs to be watched. Blood pressure, urine protein, serum platelet count, liver function tests, and other indicators may need to be checked. A premature baby will need hospital care.
How is the disease monitored? Preeclampsia does not lead to chronic high blood pressure. The risk of preeclampsia in future pregnancies is roughly 33%.
Author: Eva Martin, MD Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request
