There are some conditions that are linked to high blood pressure such as badly controlled thyroid problems and autoimmune disease. Multiple pregnancies can also increase the risk of preeclampsia. Initially, there are no symptoms and some identify it through early pregnancy checks. It usually starts with raised blood pressure. As it progresses, some people get headaches, chest pains, giddiness and blurring of vision. As it gets worse, nausea might occur. As a mother approaches eclampsia, her movements and reflexes become very brisk.