There is a lot more to pre- eclampsia than just high blood pressure. In fact, pre-eclampsia can cause problems in virtually any part of your body. And it affects different women in different ways. 
Pre-eclampsia can affect you as well as your unborn baby. That's because it starts with a problem in the organ that joins you and your baby in your womb. That organ is called the placenta.
No one knows exactly how the unhealthy placenta makes you ill. But experts think that harmful chemicals from the placenta get back into your bloodstream. Then they damage the lining of your blood vessels. 
Because of the damage to your blood vessels, you get:
High blood pressure
Protein leaking out of your blood vessels and into your urine
Water leaking out of your blood vessels, causing swelling in your face, hands, or feet (but this doesn't always happen).
These changes in themselves don't make you ill. But they can lead to serious problems (complications), such as: 
Eclampsia (seizures or fits)
Problems with the way your blood clots, leading to heavy bleeding (haemorrhage)
Fortunately, these problems are now quite rare in the UK. This is partly because the care women get during and after pregnancy helps to pick up and treat pre-eclampsia before it gets dangerous. It may also be because women who get pregnant in the UK are healthier than they used to be.
Haemorrhage is a word doctors use for bleeding. Any time blood escapes from a vessel, it's called a haemorrhage.
high blood pressure
Your blood pressure is considered to be high when it is above the accepted normal range. The usual limit for normal blood pressure is 140/90. If either the first (systolic) number is above 140 or the lower (diastolic) number is above 90, a person is considered to have high blood pressure. Doctors sometimes call high blood pressure 'hypertension'.
Your kidneys are organs that filter your blood to make urine. You have two kidneys, on either side of your body. They are underneath your ribcage, near your back.
Your liver is on the right side of your body, just below your ribcage. Your liver does several things in your body, including processing and storing nutrients from food, and breaking down chemicals, such as alcohol.
A lot of your body's tissues are made out of proteins. Proteins can be made in your cells. Proteins are also part of the food you eat, particularly meat and dairy products. Your body breaks down the protein you eat into amino acids. Your cells then use these amino acids to build new proteins, which make up muscles, joints, hair and other parts of your body.
A seizure (or fit) is when there is too much electrical activity in your brain, which results in muscle twitching and other symptoms.
You have a stroke when the blood supply to a part of your brain is cut off. This damages your brain and can cause symptoms like weakness or numbness on one side of your body. You may also find it hard to speak if you've had a stroke.
For more terms related to Pre-eclampsia
For references related to Pre-eclampsia click here