|What is pre-eclampsia?|
Pre-eclampsia means ‘before eclampsia’. It is a condition that only occurs in pregnancy. In some cases, pre-eclampsia may progress to a serious condition known as eclampsia.
Pre-eclampsia is a combination of:
Mild pre-eclampsia does not have any symptoms. It is usually picked up at your routine antenatal appointments.
The exact cause of pre-eclampsia is not understood.
However, it is thought that a problem develops with the blood vessels in the placenta, causing it to be underdeveloped. Researchers have discovered that levels of the hormone (activin A) are raised in the bloodstream of women with pre-eclampsia, but the reason for this is unknown.
More serious symptoms may develop as pre-eclampsia progresses and affects both the mother and the unborn baby. Affecting at least 5-8% of all pregnancies, it is a rapidly progressive condition
Around one in 200 (0.5%) women develops severe pre-eclampsia. The symptoms tend to occur later on in pregnancy but can occur for the first time after birth.
Who gets pre-eclampsia?
|Any pregnant woman can develop pre-eclampsia. It occurs in about 1 in 14 pregnancies. However, you have an increased risk of developing pre-eclampsia if you: |
How is pre-eclampsia detected?
|Hypertension (high blood pressure)|
Unless her blood pressure is very high, a woman will not be aware that it has increased. As a general rule a blood pressure greater than 140/90mmHg in pregnancy is considered to be raised.
Very high blood pressure (greater than 170/110mmHg)
Often accompanied by headaches and the appearance of flashing lights before the eyes. Measuring a woman's blood pressure is an essential part of any antenatal clinic visit.
Protein in the urine
This is detected by your doctor or midwife by using a special stick to dip into a clean sample of urine. There are other causes of proteinuria but pre-eclampsia is the cause with most significance for the mother and foetus.
Sudden or insidious weight gain with swollen hands, feet, face or other parts of the body
Some swelling is normal in pregnancy but it should prompt a woman to have her blood pressure and urine checked.
Pain in the right upper abdomen
May indicate involvement of the liver, which in severe cases can be complicated by an imbalance of the coagulation system that causes an increased or decreased ability of the blood to clot.
Headaches, fatigue, and pains in the upper abdomen
These are all symptoms of the more severe stage of the condition.
Pre-eclampsia is often subdivided into mild, moderate and severe depending on the level of blood pressure and the involvement of other organs in the disease process. In the worst cases, pre-eclampsia can develop into eclampsia, a situation where the mother has a convulsion.
Fortunately, eclampsia is rare, but this is largely because women with pre-eclampsia are usually detected and treated before eclampsia can develop.
All the symptoms will disappear after the delivery and normally the blood pressure and protein level in the urine will be back to normal after a maximum of two weeks.
Pre-eclampsia can develop anytime after 20 weeks of pregnancy. Pre-eclampsia is present if:
Symptoms of pre-eclampsia and how does it progress?
|There are no symptoms in the early stages of pre-eclampsia, and it can only be detected by regular antenatal check-ups. It is natural for many women to experience increased blood pressure during their pregnancy, but this alone is not a sure sign of pre-eclampsia. Regular antenatal check ups can determine whether your increased blood pressure is as a result of pre-eclampsia, usually by the checking for protein in your urine.|
The severity of pre-eclampsia is usually (but not always) related to the blood pressure level. You may have no symptoms at first, or if you have only mildly raised blood pressure and a small amount of leaked protein in your urine. If pre-eclampsia becomes worse, one or more of the following symptoms may develop. See a doctor or midwife if any of these occur.
Regular checks may be all that you need if pre-eclampsia remains relatively mild. If pre-eclampsia becomes worse, you are likely to be admitted to hospital. Tests may be done to check on your well-being, and that of your baby. For example, blood tests to check on the function of your liver and kidneys. Also, an ultrasound scan is usual to see how well your baby is growing.
If your blood pressure cannot be controlled, your obstetrician may suggest that you have your labour induced or that you deliver your baby by caesarean section.
Understanding blood pressure readings
|Normal blood pressure is below 140/90 mmHg. The first number (systolic pressure) is the pressure at the height of the contraction of the heart. The second number (diastolic pressure) is the pressure in the arteries when the heart rests between each heart beat. |
Is pre-eclampsia the same as high blood pressure of pregnancy?
No. Many pregnant women develop mild high blood pressure. Most do not have pre-eclampsia. With pre-eclampsia you have high blood pressure, plus protein in your urine, and sometimes other symptoms and complications listed above. About 1 in 5 pregnant women with high blood pressure progress to pre-eclampsia.
Therefore, if you develop mild high blood pressure, it is vital that you have regular ante-natal checks which can detect pre-eclampsia, if it occurs, as early as possible.
What is the treatment for pre-eclampsia?
Delivering the babyThe only complete cure is to deliver the baby. At delivery the placenta (often called the afterbirth) is delivered just after the baby. Therefore, the cause of the condition is removed. After the birth, the blood pressure and any other symptoms in the mother usually soon settle.
Attempts will be made to manage your pre-eclampsia until a delivery after 36 weeks of pregnancy can be achieved. Treatment is often aimed at lowering your blood pressure, which includes bed rest and medication, usually in hospital where your condition can be monitored constantly.
It is common practice to induce labour if pre-eclampsia occurs late in the pregnancy. A caesarean section can be done if necessary. The risk to the baby is small if he or she is born just a few weeks early. However, a difficult decision may have to be made if pre-eclampsia occurs earlier in the pregnancy. The best time to deliver the baby has to balance several factors which include:
As a rule, if pre-eclampsia is severe, then delivery sooner rather than later is best. Pre-eclampsia is therefore the cause of around 15% of premature births. If the pre-eclampsia is not too severe, then postponing delivery until nearer full term may be best.
Will pre-eclampsia develop in my next pregnancy?