Effects on blood vessels and body fluids
A well-known phenomenon in a woman who develops hypertension during pregnancy is that the muscular walls of the blood vessels all over her body contract, so the space inside the vessels becomes smaller. (The technical name for this is generalised vasoconstriction.) The constriction causes high blood pressure in the blood vessels, and this is one reason why fluid from the blood is pushed out through the vessel walls and collects in the woman's tissues.
What is the name for the swelling due to fluid collecting in the tissues and where is the swelling most often visible in pregnant women with hypertension?
The swelling is called oedema and is a warning sign of hypertension in pregnancy. It is most often see in the lower legs, ankles and feet; also the hands, and in the most severe cases in the face and back.