Preeclampsia is a medical condition that occurs during pregnancy, usually in the second half of pregnancy (from around week 20 onwards; most cases occur between weeks 24 and 26) or shortly after birth.
Causes and risk factors for preeclampsia
The exact cause is not fully known. It is thought that preeclampsia occurs because the placenta does not develop properly due to problems with the blood vessels that supply it (NHS-UK, 2015).
Mild preeclampsia occurs in about 6% of pregnancies, while more severe forms occur in around 1–2% of pregnancies.
There are many factors that can increase the chances of developing preeclampsia (NHS-UK, 2015):
– diabetes, high blood pressure, or kidney disease before pregnancy
– pre-existing conditions such as lupus and antiphospholipid syndrome
– preeclampsia in a previous pregnancy
Other factors that can increase the chances of developing preeclampsia include:
– this is your first pregnancy (it is more common in a first pregnancy)
– a family history of preeclampsia (e.g., your mother or sister has preeclampsia)
– age over 40
– it has been more than 10 years since your last pregnancy
– pregnancy with twins or triplets
– body mass index >35 (BMI)
If two or more of these factors are present, there is a higher likelihood of developing preeclampsia.
Early signs of preeclampsia
The early signs of preeclampsia are high blood pressure (hypertension) and protein in the urine (proteinuria). You will probably not notice these signs yourself, but your blood pressure will be measured and your urine tested at your pregnancy check-ups. High blood pressure affects 10–15% of all pregnant women, so on its own it does not indicate preeclampsia. However, if protein is found in the urine at the same time as high blood pressure, this may be an indicator of preeclampsia (NHS-UK, 2015).
Symptoms of preeclampsia
As preeclampsia progresses, it can cause the following symptoms (NHS-UK, 2015):
– severe headaches
– vision problems, such as blurring or seeing flashing lights
– severe heartburn / pressure in the upper abdomen
– pain under the ribs
– nausea or vomiting
– excessive weight gain due to fluid retention
– feeling unwell
– swelling of the feet, ankles, face, and hands
If preeclampsia occurs, you need to seek medical help. Without prompt treatment, preeclampsia can cause a number of serious complications, such as:
– eclampsia (seizures)
– HELLP syndrome
– stroke
– blood clotting disorders
– problems with certain organs (pulmonary oedema, kidney and liver failure)
Signs of preeclampsia in the unborn baby
The main sign of preeclampsia in the unborn baby is slow growth. This is due to reduced blood flow through the placenta to the baby. The baby receives less oxygen and fewer nutrients than it should, which can affect its development. The diagnosis is intrauterine fetal growth restriction – IUGR (NHS-UK, 2015). If your baby is growing more slowly than expected, this will be noticed during a medical examination during pregnancy.
Diagnosing and treating preeclampsia
Preeclampsia is diagnosed during routine pregnancy check-ups. During these appointments, your blood pressure is measured regularly and a urine sample is tested to see whether it contains protein.
Preeclampsia can only be cured by giving birth. Once you are diagnosed, you will remain in hospital until delivery, as your baby’s condition and your blood pressure are monitored regularly, and tests (blood, urine) are taken to detect any possible deterioration.
