Ovarian vein thrombosis in the postnatal period.

Although ovarian vein thrombosis (OVT) is classically considered a puerperal pathology, it can also occur in nonpuerperal settings such as endometritis, pelvic inflammatory disease, Crohn's disease, pelvic or gynaecological surgeries and thrombophilia. Hypercoagulation conditions such as antiphospholipid syndrome, systemic lupus erythematosus, factor V Leiden and protein C and S deficiency are all recognised risk factors. It is also a known complication during pregnancy often presenting with fever and lower abdominal pain within weeks after delivery. Its incidence is exceedingly rare, occurring in 0.05% of all pregnancies that result in live births and peaking around 2-6 days after delivery. Its preferential involvement of the right ovarian vein may be explained by the compression of the inferior vena cava and the right ovarian vein due to dextrorotation of the uterus during pregnancy. Furthermore, antegrade flow of blood and multiple incompetent valves in the right ovarian vein favours bacterial infection. Complications may include sepsis and thrombus extension to the inferior vena cava or left renal vein and rarely, pulmonary embolism. The authors present the case of a 27-year-old woman with lower abdominal pain 5 weeks after an elective caesarean section. Although the diagnosis of postpartum endometritis was initially considered, a CT suggested a right OVT. She commenced treatment with low-molecular weight heparin. A high index of clinical suspicion is required in order to establish the diagnosis of this rare cause of abdominal pain, which can mimic an acute abdomen. © BMJ Publishing Group Limited 2021. No commercial re-use. See rights and permissions. Published by BMJ.