Primary objective: To determine whether pregnancy increases the risk of recurrent CeAD and delayed stroke in women with prior CeAD based on long-term data.

Methods: Multicentric, observational case-control study based on pooled individual patient data from several stroke centers.

Primary endpoint: Primary composite outcome measure includes the following outcomes: (i) occurrence of recurrent CeAD, (ii) occurrence of ischemic or hemorrhagic stroke, (iii) death.

Background: Cervical artery dissection (CeAD) is a leading cause of stroke in women of childbearing age. Among the population with an initial CeAD, about 9% show a recurrence event (a range from 0 to 25% has been reported). Recurrence of CeAD can occur for several years after the initial event. CeAD has been shown to occur in association with pregnancy, and the postpartum period, yet it remains unclear whether pregnancy increases the risk of recurrence or delayed stroke. Previous studies on this subject are either based on small sample sizes or lack long-term data.

Objective: The investigators want to determine whether pregnancy increases the risk of recurrent CeAD and delayed stroke in women with prior CeAD based on long-term data.

Furthermore, it will be investigated whether the mode of delivery affects recurrence and if dissections occurred during a particular phase of a woman's reproductive process. The investigators will also investigate if women actively decided against another pregnancy due to the initial CeAD.

Methods: This study will be a multicenter, exploratory case-control study using pooled individual patient data from several stroke centers. The data will be obtained through review of medical records and patient interviews. The study will include all women with any prior CeAD who have had long-term follow-up (at least 6 months, with no upper limit), including information about pregnancy and recurrence of CeAD.

Primary endpoint is a composite outcome measure which consists of (i) occurrence of recurrent CeAD, (ii) occurrence of ischemic or hemorrhagic stroke, (iii) death. Secondary endpoints are the individual components of the primary endpoint and functional outcome assessed by the modified Ranking scale.

Statistical analysis will be used to determine the odds of the primary and secondary endpoints in women who had subsequent pregnancies compared to those who did not.

Inclusion Criteria:

• female
• prior symptomatic cervical artery dissection (= index CeAD)
• at least one long-term follow-up visit (at least 6 months after the initial event)
• with information available on outcome events:
• recurrent dissection
• ischemic stroke
• hemorrhagic stroke
• functional outcome assessed by mRS score
• with data on pregnancy after the initial event
• at least 18 years old at the initial event

Exclusion Criteria:

• Male patients
• Age <18 years
• No long-term follow-up available or long-term follow-up < 6 months after initial event
• No data on pregnancy after initial event available

Female patients aged ≥18 years with prior CeAD.