[Ovarian hyperstimulation syndrome and thrombosis. Apropos of a case of thrombosis of the internal jugular vein. Review of the literature]

Abstract

Thrombosis of the internal jugular vein was associated with a severe syndrome of ovarian hyperstimulation. After in vitro fertilization, a twin pregnancy was obtained in a 31-year-old patient with severe endometriosis. On the day of follicle collection, plasma oestradiol was 3050 mg/ml. Ten ovocytes were collected and 3 embryos were implanted. A syndrome of severe ovarian hyperstimulation (ascites, pleural effusion) developed 3 weeks later and symptomatic treatment was given. Phlebitis of the upper left limb was diagnosed at 9 weeks amenorrhoea and echo-Doppler confirmed the diagnosis of subclavian and internal jugular venous thrombosis. Search for a cause was negative excepting a frank drop in protein S activity to 35%. Post-partum assay and assay in family members confirmed that the deficiency was acquired during pregnancy. The clinical course was favourable with anticoagulant therapy (heparin, then low-molecular weight heparin). Intra-uterine death of one of the fetuses occurred at 21 weeks amenorrhoea and a 2,550 g girl was born by vaginal delivery at 36 weeks. The Apgar score at birth was 10/10. In a review of the literature on vascular events in fertilization, programmes showed that severe syndromes of ovarian hyperstimulation, endogenous hyperestrogenism, multiple pregnancy and predominance of upper limb are the most frequently observed criteria. We emphasize the importance of preventing these thromboembolic events with subcutaneous heparin during the first trimester of pregnancy followed by low-molecular weight heparin, particularly in patients with a history of thromboembolism and/or patients with severe ovarian hyperstimulation.