Septic pelvic thrombophlebitis and septic ovarian vein thrombophlebitis are seen principally as complications of puerperal infections and of septic abortions. It occurs approximately 1 in 3,000 vaginal deliveries and 1 in 2000 times Caesarean sections. Factors contributing to the pathogenesis of gonadal vein thrombophlebitis include stasis of blood, increased levels of procoagulants, and endothelial damage.
Gonadal vein thrombophlebitis can also be seen after gynaecological surgery or pelvic inflammatory disease. Anaerobic bacteria are often involved, resulting in septic pelvic thrombophlebitis. Bacterial organisms spread within thrombosed veins. Intermittent septicaemia results in septic pulmonary emboli and metastatic abscesses.

Clinically, the patient with septic pelvic thrombophlebitis most present with fever of unknown origin in the postpartum period. Once the diagnosis is suspected, the administration of heparin quickly reduces the fever. Traditionally, resolution of the fever within 24 hours of heparin administration confirms the diagnosis thrombophlebitis.