In this high pressure environment fluid seeps into the tissues resulting in Edema. This swelling is normally seen in the ankles and lower back. The body now is forced to redistribute it's blood flow. Areas such as the skin are last to recieve oxygenated blood. Fibrinogen is released and causes large quantities of fibrin to be release.
Pregnancy is a time where there is an abundance of fibrin.
Fibrin goes to the massive trauma area and in the process of clot building clotting factors are used up . Excess fibrin begins to degrade. In so doing anti coag. Thrombocytopenia is the increased consumption or destruction of platelets. Platelets, fibrin, or both accumulate wherever the endothelial cells are damaged or lost.