Superficial thrombophlebitis may occur spontaneously, often in pregnant or postpartum women or in individuals with varicose veins, or it may be associated with trauma, as with a blow to the leg or following intravenous therapy with irritating solutions. It also may be a manifestation of systemic hypercoagulability from abdominal cancer such as carcinoma of the pancreas
Superficial thrombophlebitis related to a PICC may be associated with occult DVT in about 20% of cases, but occult DVT is much less commonly associated with spontaneous superficial thrombophlebitis of the saphenous vein (about 5% of cases). Pulmonary emboli are exceedingly rare and occur from an associated DVT