Association between combined oral contraceptive prescription and cervical artery dissection: A retrospective cohort study

Background: To date, research has identified positive associations between combined oral contraceptives (COCs) and adverse vascular events, however, evidence regarding the possible association with cervical artery dissection (CeAD) remains limited. We tested the hypothesis of a positive association between COCs and CeAD within one year following COC initiation compared to matched controls initiating intrauterine devices (IUDs), as measured by risk ratio (RR). Methods: We queried de-identified United States health records data (TriNetX, Inc.) from 2014 to 2024 for females aged 15-50 years without previous cerebrovascular disease or CeAD, creating mutually exclusive cohorts initiating either COCs or IUDs. We used propensity matching to control for variables associated with CeAD. Our primary outcome included the RR for CeAD within one year follow-up. We secondarily explored cumulative CeAD incidence and RR of stroke, also examining outcomes for females with >= 2 COC prescriptions (COC2). Results: After matching there were 214,020 patients per cohort (mean age 31 years). The incidence and risk of CeAD was greater among those prescribed COCs compared to matched controls with IUDs [95 % CI] (COCs: 0.016 %, IUDs: 0.008 %; RR 1.94 [1.10,3.43]; P = 0.0195). A similar association was observed for stroke (COCs: 0.106 %, IUDs: 0.057 %; RR = 1.86 [1.49,2.32]; P < 0.0001). The secondary COC2 analysis revealed similar findings. Conclusions: The present findings suggest that females prescribed COCs have an increased risk of CeAD and stroke compared to matched controls using IUDs. These observations should be viewed as preliminary, require corroboration by other studies, and in isolation do not replace the broader clinical and shared decision-making regarding contraceptive use.