From Dr. Laima Siddiqi – Nadery
There are different classes of high blood pressure during pregnancy. The focus today is on a particular type called pre-eclampsia.
What is pre-eclampsia?
Pre-eclampsia is a new onset of high blood pressure with protein in urine after 20 weeks of pregnancy. Some patients may have high blood pressure with organ damage (i.e., affecting the liver, kidney, platelets, lungs and brain) with or without proteinuria (the presence of abnormal quantities of protein in the urine) which may indicate damage to the kidneys!
Risks of developing pre-eclampsia
Women with one or more of the following characteristics are at increased risk for developing pre-eclampsia: First pregnancy, high blood pressure or diabetes prior to pregnancy, kidney disease, lupus, diabetes developed during pregnancy, multiple pregnancies (twins or triplets), a family history (sister or mother) of pre-eclampsia, history of pre-eclampsia in previous pregnancies, overweight, women under age 20 and women over 35.
Causes of pre-eclampsia
It is not fully understood why pre-eclampsia occurs. It is probably abnormalities in the growth of blood vessels of the uterus and placenta early in pregnancy. This might trigger a cascade of events that eventually causes pre-eclampsia. Signs and symptoms of pre-eclampsia occur mainly due to changes inside the small arteries that decrease blood flow to maternal organs such as the kidney, brain, liver and the placenta. Why this happens to some women and not others is not completely known.
Symptoms and signs of pre-eclampsia
Maternal (mother) – Most women with pre-eclampsia have mildly elevated blood pressure and sometimes protein in their urine. They do not experience any symptoms. Therefore, frequent visits to the specialist and/or gynaecologist are scheduled to monitor the blood pressure in the last half of pregnancy, even if there are no complaints. However, pre-eclampsia can progress and severely worsen!
Severe symptoms can be persistent severe headache, visual problems, progressive shortness of breath and abdominal pain. A sign that pre-eclampsia has progressed to the severely are blood pressure ≥160/110 mmHg (a pressure unit), abnormal kidney tests, low platelet count, liver abnormalities and/or fluid in the lungs.
Foetal (the unborn baby) – Pre-eclampsia can diminish the capacity of the placenta to provide adequate nutrition and oxygen to the baby, which will cause a slowed growth of the baby, decreased amount of (amniotic) fluid around the baby and decreased blood flow.
How to prevent pre-eclampsia
There are no conclusive tests to anticipate occurrence of pre-eclampsia. However, pregnant women may be able to prevent this by having their blood pressure monitored by the treating physician or midwife. When diagnosed with high pressure during pregnancy, it is of utmost importance to take the medication prescribed by your treating physician. The medication prescribed is specific to high blood pressure during pregnancy as it is not always safe to use other types of blood pressure medication during pregnancy.
How to treat pre-eclampsia
The only cure for pre-eclampsia is delivery of the baby and placenta. The treatment depends on the duration of the pregnancy and whether severe symptoms of the disease are present. The gynaecologist evaluates and decides the method of delivery and when it should be initiated. If pre-eclampsia develops before the due date and there are no severe features of the disease, early intervention (delivery) does not have to take place. This will allow the baby time to grow and mature.
However, if severe symptoms of pre-eclampsia develop, premature delivery is often necessary to prevent further complications for the mother and the baby. Bed rest and medication can lower blood pressure and thus reduce the risk of complication, but these treatments do not improve the underlying abnormalities in the mother's blood vessels. Therefore, they do not prevent progression of the disease.
What happens after the delivery?
High blood pressure and protein in the urine will resolve within a couple of days after delivery. However, even after pre-eclampsia resolves, women who had pre-eclampsia are at higher risk for developing cardiovascular disease later in life than women who did not have pre-eclampsia. They should discuss this risk with their health care provider and monitor their blood pressure at least once a year. Lifestyle adjustments – namely a healthy diet, avoiding obesity and smoking, and management of elevated lipids (high cholesterol), diabetes and high blood pressure (if these disorders develop) – will reduce the risk of cardiovascular problems.
