Recent research is highlighting a potential concern for young women using combined oral contraceptives (OCs). A study presented at the European Stroke Organisation Conference (ESOC) 2025 reveals a significant association between the use of these contraceptives and an increased risk of cryptogenic ischemic stroke (CIS). This type of stroke, which has no identifiable cause, accounts for a substantial proportion of strokes in young adults, making this finding particularly relevant.
The study, known as the SECRETO study, involved 268 women aged 18-49 who had experienced CIS, comparing them to a control group of 268 age-matched women without stroke. Researchers discovered that 66 of the stroke patients and 38 of the control participants were using combined OCs. After accounting for factors like age, hypertension, smoking, migraine with aura, and abdominal obesity, the study found that OC use was linked to a threefold increase in the odds of CIS. This connection remained strong even after considering other known risk factors, suggesting that the increased stroke risk may occur independently through other mechanisms, possibly genetic or biological.
Dr. Mine Sezgin, the lead author of the study from Istanbul University, emphasized that these results confirm earlier evidence linking oral contraceptives to stroke risk. She also noted the importance of the finding that the association persists even when accounting for other risk factors, suggesting that there may be additional mechanisms involved. The majority of OC users in the study were taking ethinylestradiol-based formulations, with a median dose of 20 micrograms.
These findings add to the existing body of evidence that connects hormonal contraception to vascular risks in women of reproductive age. While previous studies have also suggested a link between combined OCs and stroke risk, this study specifically focuses on cryptogenic stroke in young women, adding a layer of specificity to the research.
Another recent study from Denmark, published in BMJ in February 2025, also supports these concerns. This study, which tracked over two million women, found that combined estrogen-progestin contraceptives, as well as progestin-only products, were associated with a slightly increased risk of ischemic stroke and myocardial infarction (MI). Compared to non-users, there were 21 extra ischemic strokes and 10 extra MIs per 100,000 person-years in current users of combined estrogen-progestin contraceptives. While the absolute excess risks were low, the researchers stressed that clinicians should consider the potential risk of arterial thrombosis when prescribing hormonal contraceptives.
These studies highlight the need for increased awareness and careful evaluation of stroke risk in young women, especially those with additional risk factors. While the overall risk remains low, the potential for a threefold increase in cryptogenic stroke risk associated with combined oral contraceptives warrants further investigation and consideration in prescribing practices. Further research is planned to explore the underlying biological and genetic mechanisms that may contribute to this increased risk, which could lead to a better understanding of how hormonal contraceptives independently elevate stroke risk. In the meantime, women should discuss the potential risks and benefits of different contraceptive options with their healthcare providers to make informed decisions about their reproductive health.
