Previous Cerebral Venous Sinus Thrombosis in Pregnancy: Clinical Challenges and Outcomes – A Case Report

Abstract

Background

Cerebral venous sinus thrombosis (CVST) is a rare vascular disorder caused by partial or complete occlusion of the dural venous sinuses. It accounts for approximately 0.5–3% of all cerebrovascular occlusive diseases and is associated with significant morbidity and mortality. The incidence is higher in women of reproductive age, particularly during pregnancy and among users of hormonal contraception. Prothrombotic factors such as pregnancy and hormonal contraceptive use contribute substantially to disease occurrence.

Case Illustration

A reproductive-aged woman (G4P2A1) with a two-year history of CVST presented with worsening headache at 37 weeks of gestation. The patient had a prior diagnosis of CVST and continued exposure to hormonal contraceptives despite the diagnosis. She had a history of depot medroxyprogesterone acetate (DMPA) injections prescribed by healthcare providers and combined injectable contraception used on her own initiative after being diagnosed with CVST. During pregnancy, anticoagulation management was suboptimal because warfarin therapy was continued until pregnancy was recognized and subsequently discontinued by the patient. Delivery was performed via cesarean section due to worsening headache. Postpartum symptoms were controlled with medical therapy and both maternal and neonatal outcomes were favorable.

Conclusion

Special consideration is required when administering antithrombotic therapy during pregnancy and delivery. This case highlights the importance of appropriate contraceptive counseling in women with a history of CVST and the need for pregnancy-safe anticoagulation strategies to minimize thrombotic complications and optimize maternal and fetal outcomes. Management of CVST in pregnancy should involve a multidisciplinary team to determine the safest mode of delivery and optimize maternal and fetal outcomes.

Introduction

Cerebral venous sinus thrombosis (CVST) is a vascular disorder characterized by partial or complete occlusion of the dural venous sinuses.¹ It is a rare condition, with an estimated incidence of 3–5 cases per 1 million population annually. Despite its rarity, women are three times more likely than men to develop CVST. Majority of cases occur in individuals younger than 55 years old, approximately 80% of cases occur in women of reproductive age.^2,3

CVST is closely associated with reproductive health. Gender-specific risk factors include obesity, pregnancy, puerperium, menopause, oral contraceptive use, and hormone replacement therapy. These risk factors increase risk of thrombosis, especially in women.⁴ Hormonal contraception has been identified as an important risk factor for CVST. Estrogen increases von Willebrand factor activation, elevates coagulation factors, and reduces anticoagulant factors, thereby promoting a prothrombotic state. Medroxyprogesterone acetate increases thrombotic risk through regulation of thrombin receptor expression. These prothrombotic mechanisms may exacerbate CVST.⁵

Pregnancy further contributes to thrombotic risk through physiological hypercoagulability, characterized by increased concentrations of coagulation factors, reduced fibrinolytic activity, venous stasis, and hemodynamic adaptations. In women with a previous history of CVST, these pregnancy-related changes may complicate clinical management, particularly in the presence of additional risk factors such as hormonal contraceptive exposure. Therefore, comprehensive risk assessment, appropriate contraceptive counseling, and individualized anticoagulation or thromboprophylaxis strategies are essential in this population.

This case describes pregnancy in a woman with a previous history of CVST, continued hormonal contraceptive exposure, and challenges in anticoagulation management. It highlights important clinical considerations regarding contraceptive selection after CVST, pregnancy-safe anticoagulation strategies, and multidisciplinary management to optimize maternal and fetal outcomes.

Case Illustration

A 29-year-old woman (G4P2A1) at 37 weeks of gestation with a BMI of 26.6 kg/m² (overweight) presented with worsening headache one day prior to admission. She had previously delivered two healthy infants vaginally in 2017 and 2022, each weighing approximately 3300 g, before being diagnosed with cerebral venous sinus thrombosis (CVST). She had one miscarriage requiring curettage four months before the current pregnancy. She denied experiencing labor pain or bloody show.

The patient was diagnosed with CVST approximately four years before the current pregnancy after experiencing persistent headaches for more than six months. Brain MRI and Magnetic Resonance Venography (MRV) demonstrated narrowing of the right transverse to sigmoid sinus consistent with CVST, accompanied by anatomical sinus hypoplasia (Figure 1). She had no history of smoking, hypertension, diabetes mellitus, thrombophilia, or cardiac arrhythmia. Further thrombophilia evaluation, including Protein C, Protein S, Antithrombin III, Factor V Leiden mutation, antiphospholipid antibodies, and lupus anticoagulant testing, was not performed. Since the diagnosis, she had been treated with pregabalin, amitriptyline, and warfarin.

Figure 1.

Magnetic resonance venography (MRV) demonstrating narrowing of the right transverse to sigmoid sinus (ARROW), consistent with cerebral venous sinus thrombosis, with associated anatomical sinus hypoplasia.

Regarding contraceptive history, the patient had used three-monthly injectable contraception containing depot medroxyprogesterone acetate (DMPA) since 2020, administered by a midwife. She continued hormonal contraception and subsequently used monthly combined injectable contraception containing DMPA and estradiol cypionate following curettage for miscarriage. Hormonal contraception was continued for approximately two years after the diagnosis of CVST. During this period, the patient occasionally experienced headaches.

The patient recognized her pregnancy during the first trimester, she discontinued warfarin without consulting her physician due to fear of teratogenic effects. However, she continued neurology follow-up without informing her neurologist of the pregnancy until approximately 24 weeks of gestation. During neurological evaluation, her D-dimer level was elevated at 1.03 µg/mL. Warfarin was then replaced with low-dose acetylsalicylic acid (80 mg/day).

The patient subsequently consulted a maternal–fetal medicine specialist. Ultrasound examination showed a fetus consistent with 33 weeks of gestation, with an estimated fetal weight of 1849 grams, no structural abnormalities, and normal Doppler findings in the middle cerebral, umbilical, and uterine arteries. Acetylsalicylic acid was subsequently discontinued by the neurologist in preparation for delivery, and vaginal delivery was initially recommended.

At 37 weeks of gestation, the patient presented with worsening headache. Her blood pressure was 113/77 mmHg, pulse rate was 105 beats per minute, and respiratory rate was 20 breaths per minute. On abdominal examination, the fundal height measured 31 cm and the fetal heart rate was 136–140 beats per minute. Vaginal examination revealed no cervical dilatation. No focal neurological deficits were documented on clinical examination. Because of worsening headache, delivery was performed by cesarean section. Cesarean delivery was performed under spinal anesthesia. A male infant was delivered weighing 3320 grams, with a length of 51 cm, and Apgar scores of 7 at one minute and 8 at five minutes. The patient opted for sterilization as her contraceptive method.

The patient’s postpartum condition was stable Acetylsalicylic acid was resumed on the third postoperative day after consultation with the neurologist. The patient subsequently attended regular follow-up visits with the neurology and obstetrics–gynecology departments. Her headache symptoms improved and were well controlled with medical therapy. A summary of the patient’s clinical course is presented in Figure 2.

Figure 2.

Disease progression and antithrombotic management timeline illustrating contraceptive exposure, CVST diagnosis, pregnancy course, treatment modifications, delivery, and postpartum follow-up.

Discussion

Cerebral venous sinus thrombosis is an obstruction of the dural venous sinuses of the brain. This condition disrupts venous drainage, leading to increased intracranial pressure, venous infarction, and intracranial hemorrhage. The disease was first described by the British scientist John Abercrombie in 1828. A postmortem examination of a woman with a history of seizures two weeks after childbirth revealed thrombosis in the cerebral sinuses and veins.⁶

The incidence of CVST is rare in the United States and Europe, with an annual incidence of only 0.5–1 cases per 10,000,000 people. In young adults, CVST is much more common in women than in men, with a ratio of approximately 3:1. This trend is generally associated with gender-specific risk factors, particularly prothrombotic conditions in women, such as obesity, pregnancy, the postpartum period, and menopause. The use of oral contraceptives and hormone replacement therapy is also associated with the incidence of CVST. Oral contraceptives are the second most common cause of CVST.^4,7

The diagnosis of CVST remains challenging because patients may present with a wide spectrum of nonspecific manifestations, including headache, focal neurological deficits, seizures, visual disturbances, and decreased levels of consciousness. As these symptoms overlap with numerous neurological and obstetric conditions, clinical diagnosis alone is often difficult. Consequently, neuroimaging plays a pivotal role in establishing the diagnosis and guiding management. Conventional magnetic resonance imaging (MRI) combined with magnetic resonance venography (MRV) is currently considered the imaging modality of choice for evaluating CVST. Dynamic time-resolved angiographic techniques, particularly Time-Resolved Imaging of Contrast Kinetics (TRICKS), provide rapid sequential acquisition of contrast flow through the cerebral venous system, allowing detailed assessment of venous hemodynamics while maintaining excellent spatial resolution. Compared with more invasive techniques such as catheter angiography, TRICKS offers a noninvasive method to identify the location and extent of thrombus, evaluate patent venous drainage pathways, assess temporal evolution of thrombosis, and detect associated parenchymal abnormalities. In addition, susceptibility-weighted imaging has demonstrated high diagnostic value for detecting venous thrombi and may further improve diagnostic accuracy.⁸

Estrogen has prothrombotic effects by increasing levels of von Willebrand factor and coagulation factors II, VII, VIII, and X, while decreasing fibrinolytic activity. Medroxyprogesterone acetate (DMPA) is a progestin commonly used in injectable contraception, has also been associated with increased thrombosis risk through regulation of thrombin receptor expression (OR 3.6; 95% CI 1.8–7.1).⁹

Pregnancy further increases the risk of thrombosis due to physiological hypercoagulability, including increased coagulation factors (V, VII, VIII, IX, X, XII), increased fibrinogen levels, and reduced anticoagulant activity. Hemodynamic changes and increased plasma volume during pregnancy may also contribute to venous stasis. These mechanisms correspond to Virchow’s triad: blood stasis, endothelial changes, and alterations in blood composition.^10,11

In this case, the patient had a history of using 3-month injectable contraceptives, consisting of medroxyprogesterone acetate (DMPA) for 2 years before, during, and up to 2 years after being diagnosed with CVST. A case-control study in Sweden reported that DMPA use increases the risk of acute venous thrombosis by 2.2 times (95% CI 1.3–4.0).¹² The patients also used combination injectable consisting of DMPA and estradiol cypionate, which will worsen the patient’s thrombosis. Several systematic reviews show an increased risk of venous thrombosis due to the use of combined hormonal contraceptives by 5.59 (95% CI 3.95–7.91) and 7.59 (95% CI 3.82–15.09) times.^5,13

According to WHO medical eligibility criteria, progestin injectable contraception in patients with a history of cerebrovascular disease falls into category 3, while combined hormonal contraception is classified as category 4. The use of these contraceptives in this patient reflects limited awareness among healthcare workers and patients regarding thromboembolic risks associated with hormonal contraception. Previous studies have shown that although hormonal contraception is widely used among women of reproductive age, 59.3% of healthcare workers have limited knowledge about thromboembolic risks, and only 25.1% of contraceptive users are aware of these risks.¹⁴ Inadequate post-miscarriage counseling and insufficient patient education may also contribute to inappropriate contraceptive use.^15,16

The management of acute CVST involves the administration of low molecular weight heparin (LMWH) followed by long-term vitamin K antagonists such as warfarin. However, warfarin is contraindicated in pregnancy because of its teratogenic effects, including skeletal abnormalities and nasal hypoplasia. In pregnant women, anticoagulation therapy should be continued with LMWH until the postpartum period. In this case, the patient did not inform the neurologist about her pregnancy until six months of gestation, leading to the prescription of warfarin.¹⁷ The patient subsequently discontinued warfarin due to concerns about bleeding and instead took acetylsalicylic acid starting at six months of pregnancy, resulting in suboptimal CVST management.

Once the pregnancy was disclosed to the neurologist at approximately six months of gestation, warfarin was formally discontinued and replaced with low-dose acetylsalicylic acid. Current guidelines recommend LMWH as the preferred anticoagulant during pregnancy because it does not cross the placenta and has a well-established safety profile for both mother and fetus.¹⁸ Therefore, the use of acetylsalicylic acid in this case should be interpreted as an individualized clinical decision due to coverage policy of Indonesia’s National Health Insurance rather than a guideline-recommended treatment strategy for CVST during pregnancy. This circumstance highlights the challenges that may arise when pregnancy is not recognized or communicated promptly to the treating physician.

Headache is the most common symptom of CVST and results from obstruction of the cerebral venous system and increased intracranial pressure. Venous obstruction may impair cerebrospinal fluid absorption at the arachnoid granulations, causing further elevation of intracranial pressure, which can lead to decreased consciousness and visual disturbances. The patient presented with worsening headache near term. However, repeat neuroimaging was not performed during pregnancy; therefore, it could not be determined whether the symptoms reflected progression of CVST, increased intracranial pressure, or another pregnancy-related cause of headache. These symptoms may have been triggered by discontinuation of acetylsalicylic acid prior to delivery.¹⁹

The use of acetylsalicylic acid in pregnant women increases the risk of intrapartum bleeding (OR=1.63; 95% CI, 1.30–2.05) and postpartum bleeding (OR= 1.2; 95% CI 1.07–1.34).^20,21 On the other hand, discontinuation of medication is associated with a recurrence rate 5.04 (95% CI 1.95–9.57) times more frequent in the first year after discontinuation of treatment in the form of acute attacks or chronic headaches. Therefore, the decision to discontinue antiplatelet or anticoagulant therapy before delivery should be carefully considered in pregnant women with CVST.²²

The patient delivered with cesarean section, and both mother and baby had favorable postoperative outcomes. Management of pregnancy in patients with a history of CVST requires a multidisciplinary team involving vascular neurology, fetal-maternal medicine, obstetric anesthesiology, and neonatology. The type of delivery method and timing should be thoroughly discussed with the patient and family. A history of CVST in pregnant women is not an absolute contraindication for vaginal delivery. In cases with moderate increased intracranial pressure, acceleration of the second stage of labor with assisted delivery methods may be performed. However, in women at very high risk of developing high intracranial pressure (hemorrhagic transformation of CVST), cesarean delivery may be considered.¹⁷ In the present case, cesarean delivery was chosen because of worsening headache at term, which raised concern regarding possible neurological deterioration and increased intracranial pressure. Although no focal neurological deficits were documented, a multidisciplinary team considered cesarean delivery to be the safest approach for maternal management.

This case has several limitations. First, thrombophilia testing, including Protein C, Protein S, Antithrombin III, Factor V Leiden mutation, antiphospholipid antibodies, and lupus anticoagulant evaluation, was not performed; therefore, an underlying thrombophilic disorder could not be excluded. Second, repeat neuroimaging was not performed during pregnancy, limiting assessment of disease progression and preventing confirmation of active thrombotic changes as the cause of worsening headache. Third, as a single case report, the findings may not be generalizable to all pregnant women with a history of CVST. Nevertheless, this case highlights important challenges regarding contraceptive counseling, anticoagulation management, and multidisciplinary decision-making during pregnancy after CVST.

This case is important because it illustrates several clinically relevant challenges: the occurrence of CVST in a reproductive-age woman exposed to prolonged hormonal contraception, inadequate counseling regarding thromboembolic risks, suboptimal anticoagulation during pregnancy, and the diagnostic complexity of CVST due to its nonspecific presentation. Furthermore, it highlights the critical role of advanced neuroimaging techniques in establishing an early and accurate diagnosis, facilitating multidisciplinary management, and ultimately contributing to favorable maternal and neonatal outcomes despite the high-risk clinical setting.

Conclusion

Women with a history of cerebral venous sinus thrombosis require careful contraceptive counseling, individualized pregnancy-safe anticoagulation planning, and multidisciplinary management throughout pregnancy and delivery. This case highlights the potential consequences of inappropriate hormonal contraceptive use and suboptimal anticoagulation management in women with previous CVST. Early risk assessment and coordinated care involving neurology, maternal–fetal medicine, and obstetric teams are essential to optimize maternal and fetal outcomes.

Ethics Approval

Institutional approval was not required for the publication of this single-patient case report, in accordance with institutional policies and the ethical standards of the Declaration of Helsinki.

Informed Consent Patient Statement

The authors confirm that written informed consent was obtained from the patient. The patient was informed about the details of the case and provided approval for the publication of the case report, including any accompanying images. All identifying information has been appropriately anonymized to ensure patient confidentiality.

Disclosure

The authors declare that they have no competing interests.