Cortical vein thrombosis misinterpreted as intracranial haemorrhage in severe ovarian hyperstimulation syndrome: case report

European Stroke Organization guideline for the diagnosis and treatment of cerebral venous thrombosis - Endorsed by the European Academy of Neurology

The current proposal for cerebral venous thrombosis guideline followed the Grading of Recommendations, Assessment, Development, and Evaluation system, formulating relevant diagnostic and treatment questions, performing systematic reviews of all available evidence and writing recommendations and deciding on their strength on an explicit and transparent manner, based on the quality of available scientific evidence. The guideline addresses both diagnostic and therapeutic topics. We suggest using magnetic resonance or computed tomography angiography for confirming the diagnosis of cerebral venous thrombosis and not screening patients with cerebral venous thrombosis routinely for thrombophilia or cancer. We recommend parenteral anticoagulation in acute cerebral venous thrombosis and decompressive surgery to prevent death due to brain herniation. We suggest to use preferentially low-molecular weight heparin in the acute phase and not using direct oral anticoagulants. We suggest not using steroids and acetazolamide to reduce death or dependency. We suggest using antiepileptics in patients with an early seizure and supratentorial lesions to prevent further early seizures. We could not make recommendations due to very poor quality of evidence concerning duration of anticoagulation after the acute phase, thrombolysis and/or thrombectomy, therapeutic lumbar puncture, and prevention of remote seizures with antiepileptic drugs. We suggest that in women who suffered a previous cerebral venous thrombosis, contraceptives containing oestrogens should be avoided. We suggest that subsequent pregnancies are safe, but use of prophylactic low-molecular weight heparin should be considered throughout pregnancy and puerperium. Multicentre observational and experimental studies are needed to increase the level of evidence supporting recommendations on the diagnosis and management of cerebral venous thrombosis.

The Clinical Characteristics of Acute Cerebrovascular Accidents Resulting from Ovarian Hyperstimulation Syndrome

BACKGROUND AND PURPOSE

Ovarian hyperstimulation syndrome (OHSS) is a serious complication that occurs after the ovarian-induction treatment. Acute cerebrovascular accident is one of the most dangerous manifestations of the syndrome. However, the characteristics of stroke resulting from OHSS have so far not been well summarised in any study.

METHODS

We reported 2 cases of acute cerebrovascular accidents secondary to OHSS. And then we performed a literature search for reports on this type of stroke, and summarised their characteristics.

RESULTS

Thirty-six published cases of this type of stroke were reviewed. Thirty two out of 36 (88.9%) of the women were 35 years old or younger. Stroke in 28 out of 36 (77.8%) of these cases was caused by arterial thrombosis. In 17 out of 28 cases, the involved cerebral vascular branches were mainly middle cerebral artery (MCA) and internal carotid artery (ICA). The acute cerebrovascular accidents happened 7 and 9.25 days after embryo transplantation or 8 and 8.33 days after last human chorionic gonadotropin treatment respectively. The prognosis of patients was relatively good after anticoagulation and some supportive treatments.

CONCLUSION

The MCA and ICA are easily involved in stroke resulting from OHSS. The young age may be a risk factor for developing stroke secondary to OHSS. Once thromboembolism develops, administering appropriate therapy is crucial.

Thrombosis following ovarian hyperstimulation syndrome

The aim of this review is to analyse the pathophysiology and complications of thrombosis in conjuction with ovarian hyperstimulation syndrome (OHSS) following ovulation induction and to suggest practical guidelines usefull for the prevention and treatment. Although the incidence of thrombosis varies from 0.2% among in vitro fertilization (IVF) cycles and up to 10% for severe cases of the syndrome, it represents the most dangerous complication of OHSS. Different changes in haemostatic markers have been found to create a state of hypercoagulability, but no single standard test is available to estimate the state of thrombosis. The role of markers for thrombophilia is controversial. Thromboses are mostly venous (67-75%) involving upper limbs and neck, then arterial (25-33%) which are mainly intracerebral. The predominant sites of venous thromboembolism in the upper part of the body may be explained by higher concentrations of estrogens drained through lymphatic ducts from ascites and by compression of rudimentary branchyal cysts. Once early diagnosis is established, it is crucial to use an anticoagulant treatment with heparin proceeded with thromboprophylaxis. However, identification of patients at risk and preventive measures of OHSS are the best means in reducing the risk of thrombosis after ovarian stimulation.

[Thrombosis of the jugular vein during pregnancy]

Thrombosis of the jugular vein is a rare complication during pregnancy. In most cases the thrombogenic factor was ovarian hyperstimulation syndrome occurred during the process of assisted reproductive technology or inherited or acquired thrombophilia. Authors report a case of jugular vein thrombosis occurred after in vitro fertilization. On the basis of the literature thromboprophylaxis should be indicated for patients who develop ovarian hyperstimulation syndrome, and also be considered for women with inherited or acquired thrombophilia, while undergoing assisted reproductive techniques.

Long-term complications of assisted reproductive technologies

Since the birth of the first baby through in vitro fertilisation over 30 years ago, there has been a rapid increase in the number of women using assisted reproductive technologies. New techniques are constantly being introduced and are evolving rapidly. Understanding the long-term impact of these treatments, which have been linked with several potential complications affecting the mother and the child, poses a constant challenge for the scientific community. The main complications discussed in this review include the rare but serious risk of thromboembolic disease particularly in the upper half of the body and a higher risk of pregnancy complications including abnormal placentation, miscarriage, gestational diabetes and hypertensive disorders. A link between assisted conception and a number of genital cancers particularly of the breast, ovary and endometrium has also been suggested, but the evidence is currently inconclusive. A number of foetal and neonatal complications including imprinting disorders, low birth weight, congenital malformations and growth disorders are also discussed.

[Ovarian hyperstimulation syndrome: pathophysiology, risk factors, prevention, diagnosis and treatment]

The ovarian hyperstimulation syndrome is a major complication of ovulation induction for in vitro fertilization, with severe morbidity and possible mortality. Whereas its pathophysiology remains ill-established, the VEGF may play a key role as well as coagulation disturbances. Risk factors for severe OHSS may be related to patients characteristics or to the management of the ovarian stimulation. Two types of OHSS are usually distinguished: the early OHSS, immediately following the ovulation triggering and a later and more severe one, occurring in case of pregnancy. As no etiologic treatment is available, the therapeutic management of OHSS should focus on its related-complications. Thrombotic complications that can occur in venous or arterial vessels represent the major risk of OHSS, possibly conducting to myocardial infarction and cerebrovascular accidents. Once the OHSS is diagnosed, prevention of thrombotic accidents remains the major issue.

The “ART” of thromboembolism: A review of assisted reproductive technology and thromboembolic complications

Since its development over 25 years ago, the use of assisted reproductive technology (ART) is on the increase. Along with its use, are also reports of thromboembolic complications (TEC); these events could resulted in significant maternal morbidity and even mortality. In this article, we reviewed the general principles of ART. We also performed a search of all published cases of TEC associated with ART, and summarized the results of studies investigating underlying hemostatic changes with ART. The goal of this article is to provide non-fertility specialists an understanding of ART, so as to better manage TEC when they occur in predisposed patients. The most common ART procedure performed today, is in-vitro fertilization-embryo transfer (IVF-ET). The process of IVF involves the use of exogeneous hormones to achieve cycle control, stimulate the ovaries, and support implantation. During this process, supraphysiological estradiol levels can result. One major complication of this intervention, ovarian hyperstimulation syndrome (OHSS), can be associated with both arterial and venous thrombotic complications. These events (especially venous thrombosis) have also been reported to occur weeks after OHSS has resolved; and they can present in unusual sites (upper extremities) resulting in treatment challenges. From current available studies, it is clear that with ovarian stimulation, both the coagulation and fibrinolytic systems are activated. This activation appears to be exaggerated and prolonged with the development of OHSS. Whether these changes are sufficient by themselves to explain the occurrence of TEC is yet unknown. Future studies should be focused on defining the frequency and risk factors of these complications; provide a closer examination of the resultant changes in the coagulation cascade during ART, OHSS and early pregnancy; and investigating the appropriate treatment and thromboprophylaxis for patients undergoing a procedure considered "elective".

Subclavian vein thrombosis following IVF and ovarian hyperstimulation: a case report

Thromboembolic phenomena are a serious consequence of assisted reproductive technology. We present a case of upper extremity deep vein thrombosis (DVT) at 7 weeks gestation following ovarian hyperstimulation syndrome (OHSS) and IVF. Three weeks after recovering from OHSS, the patient presented with left neck pain and swelling. Ultrasound revealed a thrombus in the left jugular vein and left subclavian vein. Low molecular weight heparin (LMWH) was initiated with symptom resolution within 1 week. The patient remained on LWMH throughout her pregnancy and delivered at term. A literature review showed 97 published cases of thromboembolism following ovulation induction. A majority of these cases was associated with OHSS and pregnancy and the site of involvement was predominantly in the upper extremity and neck. Infertility physicians and obstetricians should be aware of this complication and keep in mind that it may occur weeks after resolution of OHSS symptoms.

In vitro fertilization-induced alterations in coagulation and fibrinolysis as measured by thromboelastography

Supraphysiologic increases in estrogen produced by in vitro fertilization (IVF) promote the expression of hemostatic markers. Although quantitative studies of individual markers have been performed during IVF, their results are conflicting and do not reveal the qualitative effect of each marker on the overall coagulation and fibrinolytic processes. Thrombelastograph (TEG) coagulation analysis, by contrast, provides a global measure of coagulation and fibrinolysis and can indicate the relative contributions of clotting factors, fibrinogen, and platelets to each process. We studied the serum estrogen concentrations and TEG variables in 24 women at the beginning and conclusion of an IVF stimulation cycle. Serum estradiol (E(2)) concentrations (mean +/- SD) increased from 26.9 +/- 8.6 to 2098 +/- 913 pg/mL (P < 0.005) at baseline and oocyte retrieval, respectively. The measured TEG indices demonstrated alterations in coagulation rather than fibrinolysis. Although significant changes were noted in both the clot formation time and the coagulation index (P < 0.005), all TEG values remained within the normal range. In addition, an increased role of fibrinogen in promoting clot strength was observed. These findings may assist in the treatment of IVF patients who ultimately develop thromboembolic complications as a result of ovarian hyperstimulation. IMPLICATIONS. The dramatic changes in estrogen produced by in vitro fertilization therapies result in hemostatic marker alterations. Thrombelastograph coagulation analysis, which provides a global assessment of these changes, demonstrated significant alterations in two coagulation indices (clot formation time, coagulation index), although all variables remained within normal limits. The relative importance of fibrinogen versus platelets in determining clot strength was observed. No significant alterations in fibrinolysis were detected.